Push button assembly

Abstract

A button assembly for a substrate, the button assembly comprising a chassis mounted to the substrate through an aperture in the substrate, a movable lens cap mounted for movement relative to the chassis, a bezel mounted to the chassis to constrain movement of the movable lens cap away from the chassis, one or more sensors operable to sense the movable lens cap and a membrane attached to the bezel and to the movable lens cap.

Description

[0001] BUTTON ASSEMBLY

[0002] Technical Field of the Invention

[0003] The present invention relates generally to the field of button assemblies, in particular to a button assembly for a substrate. Such a button assembly may have applications in the entertainment, defence, aerospace, medical or other industries Background to the Invention

[0004] Machines, such as electronic machines, having buttons are known and used for a variety of purposes and in a variety of industries, e.g. entertainment, defence, aerospace and medical. Such machines typically include input devices which allow a user to interact with the machine.

[0005] Early input devices for use in such machines have included purely mechanical buttons. Although purely mechanical buttons are enjoyed by users due to their tactile feel, a disadvantage of such buttons is that they do not display dynamic media content. Thus, other input devices have been developed which have included liquid crystal display (LCD) decks with touch sensors. Whilst LCD decks with touch sensors can display dynamic media content, a disadvantage of such input devices is that they lack the tactile feel of mechanical buttons.

[0006] Accordingly, more recent input devices include mechanical buttons mounted through holes in the cover layer of a machine. This provides both the tactile feel of the mechanical button as well as a means for displaying dynamic media content. One problem with this solution is material ingress through the holes is difficult to prevent and can result in damage to the machine. Known button assemblies circumvent this issue by sealing an upper side of the button and providing drain openings above the cover layer to allow any material, particularly liquid to drain out of the button above the cover layer. However, small drain openings will not allow liquid to drain effectively, sometimes even if flushing cleaning agents or cleaning liquids are used.

[0007] Further, as such button assemblies do not have a low profile, they can be cumbersome and inelegant in design. Also, with button assemblies having a significant depth, any display may require positioning further away from the surface of the button assembly than is desirable for optimum viewing of the displayed image. This can causeissues with the user view through the surfaces of the button, allowing the user to see the workings of the button and / or creating undesirable visual effects.

[0008] It is an object of the present invention to provide a button assembly that at least partially overcomes or alleviates the above issues.

[0009] Summary of the Invention

[0010] According to an aspect of the present invention there is provided a button assembly for a substrate, the button assembly comprising:

[0011] a chassis mounted to the substrate through an aperture in the substrate;

[0012] a movable lens cap mounted for movement relative to the chassis;

[0013] a bezel mounted to the chassis to constrain movement of the movable lens cap away from the chassis;

[0014] one or more sensors operable to sense the movable lens cap; and

[0015] a membrane attached to the bezel and to the movable lens cap.

[0016] Providing a button assembly as defined with a membrane that is attached to the bezel and the movable lens cap (rather than to the chassis) renders the movable lens cap, membrane and bezel as one sealed structure which prevents liquid or particles from entering the button assembly beneath the membrane. Further, the construction does not have a secondary exit route for liquid or particles which may enter above the membrane. The button assembly therefore has a self-cleaning function in which repeated depression of the button can act to eject liquid or particles which may enter above the membrane, through the entry path.

[0017] The membrane may function as a biasing member or structure to bias the movable lens cap into a ‘home’ position, away from the chassis, and / or against the constraint of the bezel.

[0018] The button assembly may further comprise one or more additional biasing members or structures to bias the movable lens cap into a ‘home’ position, away from the chassis, and / or against the constraint of the bezel. As an example, one or more springs or other return features may be provided.The button assembly may preferably be a mechanical button in which the lens cap functions as a depressible button which is movable relative to the chassis. The button assembly may be positioned relative to a substrate. The substrate may be planar. The substrate may be formed from any material including particularly plastic, glass or metal.

[0019] The button assembly may be provided above a display with at least a portion of the display viewable through the lens cap and / or other parts of the button assembly. The display may be of any type. The display may be static or dynamic. The display may comprise an electronic display screen. This may provide the ability to quickly and easily adjust the information displayed thereon. The electronic display screen may for example be an LED or LCD display screen. If the display is static, the display may comprise artwork to be viewed through the lens cap and / or other parts of the button assembly.

[0020] The button assembly may be mounted to the substrate through an aperture formed in the substrate. One or more components or parts of components may be received at least partially into or through the aperture in the substrate.

[0021] The lens cap is preferably a floating component provided relative to and depressible relative to the chassis.

[0022] A controller and / or control layer may be provided in the button assembly. In one form, a PCB with electronics and at least one sensor may be provided to monitor the position of the lens cap to determine if the lens cap has been pressed or not. In some cases, the determination as to movement of the lens cap may be a binary determination, in other words sensing whether the lens cap has been depressed or not and in other cases, the determination may be more complex such as for example determining the degree to which the lens cap has been depressed.

[0023] The button assembly may comprise a chassis mounted to the substrate through an aperture in the substrate as described above. The mounting may be direct abutment, but one or more components may be provided between the chasses and the substrate.

[0024] The chassis of the button assembly may be or include a body. In one form, the chassis or body is mounted to the substrate through the aperture in the substrate. Thechassis or body is preferably dimensioned relative to the dimension of the aperture to limit and preferably prevent lateral movement of the chassis or body, and thereby the button assembly relative to the substrate. The chassis body may allow the lens cap to be depressed relative to the chassis body only.

[0025] The chassis and / or bezel may be provided above the substrate, or below the substrate.

[0026] The chassis or body may have any shape. The body will preferably be annular about an opening through the chassis or body when viewed in plan although the chassis or body is not required to be circular.

[0027] The chassis or body may comprise a substantially tubular portion to be received within the aperture in the substrate with the opening defined through the tubular portion. A circumferential shoulder may extend radially from the tubular portion. An underside of the circumferential shoulder will preferably abut an upper side of the substrate about the aperture in the substrate. A top gasket may be provided between the circumferential shoulder and the upper surface of the substrate.

[0028] The opening may be a central opening.

[0029] A depression or gutter may be provided radially inside the substantially tubular portion, the depression or gutter may extend substantially continuously about the chassis or body. When the button assembly is mounted relative to the substrate, the gutter may be received at least partially within the aperture in the substrate. The gutter may include an outer wall of the substantially tubular portion, and an inner wall spaced radially inwardly from the outer wall. The inner wall may preferably define the central opening through the chassis or body. The circumferential shoulder may be provided at an upper end of the outer wall, extending radially outwardly therefrom. The inner wall and outer wall may be substantially parallel to one another. A lower, linking wall may extend between lower portions of the inner wall and outer wall to form the gutter.

[0030] The controller and / or control layer may be located within the gutter. The controller or control layer may be located on or against the lower linking wall.

[0031] The at least one sensor may be located within the gutter.A lower gasket may be provided between a lower side of the chassis or body and the display to seal against the display.

[0032] The circumferential shoulder may have one or more upstands provided thereon. The one or more upstands may be configured to allow attachment of the bezel relative thereto. If circular, the one or more upstands may be externally threaded to allow an internally threaded portion of the bezel to engage therewith. Alternatively, the bezel may clip or snap fit to the chassis. This will allow removable attachment of the bezel relative to the chassis or body.

[0033] One or more portions of the body may be provided to be transparent or translucent or to form a light pipe (at least partially reflective wall portions or coatings to contain light) to direct light to an at least partially transparent escape window.

[0034] The button assembly may comprise a movable lens cap mounted for movement relative to the chassis. The lens cap may preferably span or cover the central opening provided in the chassis or body.

[0035] The lens cap may include a transverse portion to extend across the central opening in the body, preferably to a location outside the inner wall of the chassis or body. The transverse portion will preferably be shaped to correspond to the shape of the central opening but be larger in dimension. One or more depending side wall portions may be provided at the periphery of the transverse portion. In one form, a single depending side wall portion may be provided extending completely about the periphery of the transverse portion. The one or more depending side wall portions will preferably depend outside the inner wall of the chassis or body. This configuration will preferably minimise or limit lateral movement of the lens cap on the chassis or body.

[0036] A radially extending portion may be provided relative to the one or more depending side wall portions. The radially extending portions may extend radially outwardly therefrom. The radial extending portions may abut an underside of a part of the bezel when the lens cap is in the home position. In some embodiments however, a portion of the membrane may be interposed between the upper side of the radially extending portions of the lens cap and the underside of the bezel.As mentioned above, the lens cap is preferably provided in a floating configuration relative to the chassis or body. The lens cap is preferably mounted to the bezel which is in turn, mounted relative to the chassis or body. The lens cap may be mounted to the bezel via the membrane which may position and attach to the chassis or body. The membrane may bias the lens cap away from the chassis or body.

[0037] The lens cap may be transparent, partially transparent, partially opaque, or opaque.

[0038] An inner end of the membrane may attach to the side wall portions and / or radially extending portions of the lens cap. In some embodiments, the membrane may attach to an underside of the side wall portions and / or radially extending portions of the lens cap. In other embodiments, the membrane may attach to an upper side of the side wall portions and / or radially extending portions of the lens cap.

[0039] Any form of attachment may be provided between the membrane and the side wall portions and / or radially extending portions of the lens cap. The membrane may be bonded or co-moulded with the side wall portions and / or radially extending portions of the lens cap.

[0040] A contact or pressure pad or similar may be provided on an underside of the membrane and / or side wall portions and / or radially extending portions of the lens cap, particularly at an inner end of the membrane. The inner end of the membrane may be provided substantially directly below the side wall portions and / or radially extending portions of the lens cap.

[0041] The radially extending portions of the lens cap may have an inverted U-shaped configuration. The radial extending portion of the lens cap may be provided with a U-shaped configuration. The particular configuration of the radially extending portion may be dependent upon the particular type of sensor configuration which is used to detect movement of the lens cap. For example, in a physical or electrical contact embodiment, the membrane may attach to an underside of the radially extending portion and in this case, the radially extending portion may have an inverted U-shaped configuration (downwardly facing), whereas in a non-contact or proximity sensor embodiment, the membrane may attach to an upper side of the radially extendingportion and in this case, the radially extending portion may have U-shaped configuration (upwardly facing).

[0042] The U-shaped configuration may be formed from an inner wall and outer wall with a depression or channel between the inner wall and outer wall. The U-shaped configuration may provide a more secure attachment for the membrane by engaging with a correspondingly shaped portion of the membrane or a portion thereof.

[0043] In a radiative sensor embodiment, a reflective portion or surface may be provided on an underside of the radially extending portion of the lens cap to reflect radiation to a non-contact or proximity transmitter / receiver. The reflective portion or surface may be optically reflective or reflect another type of signal but will preferably depend upon the nature of the sensor used.

[0044] The lens cap may be provided in a unitary or single piece configuration. The lens cap may be moulded in a single piece.

[0045] The button assembly may preferably include a bezel mounted to the chassis to constrain movement of the movable lens cap away from the chassis.

[0046] The bezel may be releasably mounted to the chassis or body. Any mechanism may be used to mount the bezel to the chassis or body for example corresponding threaded portions, pins and openings, clips or a snap fit. The attachment mechanism to attach the bezel to the chassis or body may preferably be located at or toward an outer side of the bezel.

[0047] The bezel may include a radially inwardly extending portion which extends over an outer portion of the lens cap to constrain movement of the lens cap away from the body. The radially inwardly extending portion may abut a portion of the lens cap or a portion mounted to the lens cap, such as the membrane for example. Where the radially inwardly extending portion of the bezel abuts the membrane, the membrane may act to dampen the contact.

[0048] An inner end of the radially inwardly extending portion of the bezel may be spaced from and adjacent part of the lens cap when the bezel is attached to the chassis or body. This may provide clearance between the bezel and the lens cap. This may also provide an entry / exit opening between the bezel and the lens cap. Even if the inner endof the radially inwardly extending portion of the bezel is provided as close as possible to the adjacent part of lens, some form of clearance may still be present.

[0049] Any entry / exit opening is preferably closed when the lens cap is not pressed (normal state), and therefore does not allow liquid ingress. The gap may be enlarged or opened when the lens cap is pressed downwardly during operation.

[0050] As mentioned above, the membrane preferably attaches to the bezel. The membrane preferably attaches to the bezel at an outer side of the bezel, but inside any mounting mechanism used to mount the bezel to the chassis / body. An outer part of the membrane preferably attaches to the bezel. The membrane preferably attaches to an underside of the bezel.

[0051] Any attachment mechanism may be used. For example, the bezel and membrane may be co-moulded or bonded together. A sandwiching or compression or interference fit could be used. Preferably, the bezel and membrane are attached in a watertight and / or dust-tight configuration.

[0052] In one embodiment, a shaped depression may be provided in the bezel to receive a correspondingly shaped portion of the membrane to strengthen the attachment between the bezel and membrane.

[0053] An outer end of the membrane may be provided with an enlarged end portion to facilitate attachment between the bezel and the membrane. An inner end of the membrane may be provided with an enlarged end portion to facilitate attachment between the lens cap and the membrane.

[0054] The button assembly may include one or more sensors operable to sense the movable lens cap. The one or more sensors may preferably sense movement of the lens cap to determine when the lens cap has been depressed. Any number of sensors may be provided. Any type of sensor may be provided. A combination of sensors may be provided in some embodiments.

[0055] As mentioned above, the one or more sensors may be provided in the gutter in the chassis or body. The membrane is preferably located above the gutter, extending across the gutter from the bezel to the lens cap. This will act to protect any one or more sensor provided in the gutter and / or any other components such as the controller.Any appropriate type of sensor can be used. Some examples are:- Contact sensor such as electrical or physical contact sensor

[0056] Non-contact or Proximity such as infrared, ultrasound or the like Magnetic such as Hall effect

[0057] Stain gauge

[0058] Resistive (conductive)

[0059] Capacitive

[0060] Inductive

[0061] Optical

[0062] Any number of sensors may be provided. The sensor may detect depression. The sensor may be binary, detecting a press and release, such as a physical touch making electrical contacts or a more complex sensor may be used such as proximity sensing measuring distance, depth and / or period of depression.

[0063] The button assembly may include a membrane attached to the bezel and to the movable lens cap.

[0064] The membrane may be resilient. The membrane may be flexible. Any material may be used to form the membrane. A silicon material may be particularly preferred.

[0065] The membrane may be waterproof and / or particle proof. Preferably, the membrane may have an ingress protection rating of IP 65 or higher.

[0066] The membrane may have shape memory in order to bias the movable lens cap into a home position, abutting the bezel.

[0067] The membrane may have an enlarged inner end and / or an enlarged outer end to facilitate attachment of the membrane to the lens cap and / or bezel respectively. As mentioned above, the inner end and / or outer end of the membrane may be shaped or be provided with an engagement formation to engage with a part of the lens cap and / or bezel more securely. The central portion of the membrane may preferably be substantially planar, although as mentioned above, may be shaped (and / or have shape memory) to allow deformation of the membrane as the lens cap is pressed and released.The membrane may preferably be substantially annular in overall shape when viewed in plan with a central opening, however it is not essential that the membrane be circular as the shape of the membrane may preferably be dependent upon the shape of the lens cap and / or bezel.

[0068] The membrane may preferably be bonded or co-moulded with the lens cap and / or bezel.

[0069] When attached to the lens cap and bezel, the membrane will preferably extend radially between the lens cap and bezel to form a cavity above the lens cap / membrane / bezel and to prevent liquid and / or particulate matter entering the button assembly below the lens cap / membrane / bezel.

[0070] The lens cap and bezel are preferably liquid and / or particle proof, preferably to the same or greater degree as the membrane.

[0071] The button assembly of the invention may include an optical block to present an image or display optimally to a user. For example, an image of the display may be lifted using an optical block (bringing image to or closer to the surface of the lens cap) or a refraction block (which gives the appearance of lift depending on the angles viewed). Both methods may also make the inside edge of the button appear shallower, giving the impression that the button is shallower, or the image is higher.

[0072] The optic block may have any shape but may correspond to the shape of an underside of the lens cap and / or central opening in the body. The optic block may be mounted within the central opening in the body, beneath the lens cap. The optic block may be fixed relative to the lens cap or may move with the lens cap.

[0073] To enhance tactile feel when the lens cap is depressed / retums to the home position, the membrane may be configured to have a snap or bump-like feel. This may be achieved by providing the membrane with one or more rigidifying portions. The sensing method utilised (and the sensor used) may allow for the lens cap to have pre and post movement around the position / configuration of the lens cap or membrane when the sensor detects depression. The button assembly may have a click feel mechanism or configuration provided and then some travel after the actuation of the click feel mechanism or configuration, when depressed. Similarly, upon the release ofthe button, there may be some movement, then actuation of a click feel mechanism or configuration and then some further or final movement before rest in the home position.

[0074] Other snap / bump features may be added into the button assembly (under the lens cap and mounted for actuation by movement of the lens cap or membrane) to give a tailored tactile feel. Some examples of other or additional snap / bump features include microswitch, springs, diaphragms, or the like.

[0075] The button assembly may comprise a halo illumination configuration, preferably on or associated with the periphery of the button assembly. The halo illumination may comprise at least one light source within the button assembly and a pathway to an at least partially transparent escape window for the light to leave the button assembly.

[0076] The at least partially transparent escape window may be provided continuously about the button assembly. More than one at least partially transparent escape window may be provided spaced about the button assembly. The at least partially transparent escape window may be provided below the bezel, preferably between the bezel and the substrate. The at least partially transparent escape window may be provided as a part of the bezel and a lower side of the at least partially transparent escape window may seal against a gasket provided between the at least partially transparent escape window / bezel and the substrate.

[0077] The at least one light source may be or comprise an LED. The at least one light source may be provided within the gutter, preferably on or associated with the PCB or controller. The lower linking wall of the gutter and / or the at least one light source may not be at the same level and / or orientation as the at least partially transparent escape window. This may result in a smaller than desired percentage of light emitted by the at least one light source to be directed towards the at least partially transparent escape window.

[0078] The button assembly may comprise a light pipe to guide the light emitted to the at least partially transparent escape window of the button assembly and / or a diffuser to scatter the light emitted to the at least partially transparent escape window of the buttonassembly. This may make the halo effect more prominent and / or more efficient in terms of light emitted being directed to the at least partially transparent escape window.

[0079] The light pipe may be shaped. The light pipe may be located at least partially within the gutter. The light pipe may function to direct the light only, or the light pipe may direct and diffuse the light.

[0080] A light pipe may be used to diffuse the light with the aid of geometric features, surface finishes and / or material selection. For example, an additive such as a slightly opal white colour additive may be added into the material used to construct the light pipe.

[0081] Due to the compactness of the button assembly, the at least one light source may be located close to the at least partially transparent escape window. This can create a problem where the light does not have sufficient distance to disperse and / or mix. The result of this can be a hotspot effect.

[0082] To compensate for this, more light sources can be provided, therefor reducing the pitch and distance between the light sources. This is a more costly solution for the hotspot effect.

[0083] Another solution for the hotspot effect is to use a light source with a wider dispersion angle.

[0084] As mentioned above, the light pipe may also function as a diffuser to increase the mixing of light effect. This renders the light exiting the button assembly through the at least partially transparent escape window more even, despite the close proximity the light source may have to the at least partially transparent escape window.

[0085] Another possible issue in a button assembly is the at least one light source illuminating surfaces of the internal parts of the button and making internal parts of the button visible through the lens cap. To minimise or avoid this, an upper surface of the light pipe may be masked with an opaque (light blocking) surface, coating or effect. This opaque (light blocking) surface, coating or effect may be sprayed, masked with a covering film or component, dual moulded, or the like. The opaque (light blocking) surface, coating or effect may be black, chrome or any other colour provided that it does not transmit light through it.Due to the configuration of the lens cap / membrane / bezel and how it protects and moves, the configuration of the button assembly prevents liquid from entering the lower part of the button where more sensitive working components are located. When the lens cap is pressed, an opening between the lens cap and the bezel may open, which may allow liquid to enter, but a cavity defined by the lens cap, membrane and bezel contains the liquid above any working components of the button assembly. This liquid can’t enter the lower part of the button. Due to the nature of the membrane and the floating lens cap, even sticky liquids may not affect the button movement and / or function, unlike a traditional button which requires guiding frictional parts, which are adversely affected by ingress and sticky liquids.

[0086] In use, if the lens cap is pressed repeatedly and preferably quickly, then any liquid in the cavity will be ejected from the cavity, with the membrane functioning as a positive displacement pump. This provides a self-cleaning function when operating the button.

[0087] This does not happen with a traditional button having both entry and exit routes as there is no compression or pressure differential to move the liquid. Likewise, a conventional shallow button has very small exits (due to space constraints) for ingress and the liquid tends to stay within the cavities, as the capillary forces and surface tension of sticky liquids are greater than any removal forces (such as flushing).

[0088] With the design of the button assembly, even if the liquid in the cavity above the membrane is very sticky (or has dried) and doesn’t self-eject, then the design of the button assembly allows for a cleaning fluid / spray or water to be poured into the cavity and then press and release the lens cap multiple times, thus ejecting material through the entryway. Any remaining (now) clean water will evaporate or remain in the cavity above the membrane without effecting operation of the button assembly.

[0089] An advantage of the button assembly as described is that the button assembly keeps clean, but if it does need attention, then the button assembly does not need to be disassembled, nor are any special tools required. This cleaning operation and can be carried out by a non- skilled person.

[0090] Detailed Description of the InventionIn order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only, with reference to the accompanying drawings, of which:

[0091] Figure 1 is a sectional view of a prior art button assembly showing a vent or escape path for liquid with the button lens cap in the home position. Figure 2 shows the configuration in Figure 1 when the button lens cap is depressed.

[0092] Figure 3 is an axonometric view of a button assembly according to a contact sensor embodiment of the invention.

[0093] Figure 4 is a side elevation view of the button assembly shown in Figure 3. Figure 5 is an exploded view of the button assembly shown in Figure 3.

[0094] Figure 6 is a sectional view of the button assembly shown in Figure 3 fitted to a substrate and above a display.

[0095] Figure 7 is a detailed view of the portion identified in Figure 6 as “A”.

[0096] Figure 8 is a schematic view of the lens cap, membrane and bezel of the button assembly shown in Figure 3 showing possible bonding locations. Figure 9 shows the configuration of Figure 8 when depressed.

[0097] Figure 10 shows the configuration of Figure 8 with protected spaces.

[0098] Figure 11 shows the configuration of Figure 9 with protected spaces.

[0099] Figure 12 shows the direction of liquid flow of the configuration of Figure 8. Figure 13 is a sectional view of a button assembly with a non-contact or proximity sensor according to an embodiment.

[0100] Figure 14 is a detailed view of the portion identified in Figure 13 as “B”.

[0101] Figure 15 shows the configuration of Figure 14 with sensor signal during depression.

[0102] Figure 16 shows the configuration of Figure 15 with sensor signal in home position.Figure 17 is a schematic view of the lens cap, membrane and bezel of the button assembly shown in Figure 13 showing attachment locations.

[0103] Figure 18 shows the configuration of Figure 17 showing possible bonding locations.

[0104] Figure 19 shows the configuration of Figure 17 showing protected spaces.

[0105] Figure 20 shows the configuration of Figure 17 showing protected spaces when lens cap is depressed.

[0106] Figure 21 is a sectional view of a button assembly with an optic block to raise a displayed image according to an embodiment.

[0107] Figure 22 is a sectional view of a button assembly with a refraction block to raise a displayed image according to an embodiment.

[0108] Figure 23 is a sectional view of a button assembly with a refraction block to change apparent button depth according to an embodiment.

[0109] Figure 24 is a sectional view of an edge of a button assembly with a halo illumination configuration with limited angle.

[0110] Figure 25 shows the configuration of Figure 24 with a light pipe.

[0111] Figure 26 is a schematic illustration of a hotspot problem in a button assembly with halo illumination.

[0112] Figure 27 is a schematic illustration of the configuration shown in Figure 26 with wide angle light sources.

[0113] Figure 28 is a schematic illustration of the configuration shown in Figure 26 with light pipe diffusion to scatter the light from light sources.

[0114] Figure 29 is a schematic illustration of an edge of a button assembly with internal surfaces illuminated by light sources.

[0115] Figure 30 is a schematic illustration of the configuration shown in Figure 29 with a light pipe with opaque upper surface.Figures 1 and 2 show a prior art button assembly and the drain path for liquids. This button assembly shown in Figures 1 and 2 includes a chassis 12 to be mounted to an aperture in a substrate 11, a movable button component 9 mounted on the chassis 12 for movement, a bezel 14 mounted to the chassis 12 and a membrane 15 mounted between the chassis 12 and the movable button component 9. The membrane 15 has an outer portion spaced from the underside of the bezel 14 to create a drain opening 7. As shown in Figure 2, any liquid which has made its way into the button assembly has a drain path 8 out of the button assembly between the upper side of the membrane 15 and the lower side of the bezel 14.

[0116] Preferred embodiments and features of a button assembly 10 for a substrate 11 according to the present invention, are illustrated in Figures 2 to 30.

[0117] As shown in Figures 2 to 30, the button assembly 10 comprises a chassis 12 mounted to the substrate 11 through an aperture in the substrate 11, a movable lens cap 13 mounted for movement relative to the chassis 12, a bezel 14 mounted to the chassis 12 to constrain movement of the movable lens cap 13 away from the chassis 12, one or more sensors operable to sense the movable lens cap 13 and a membrane 15 attached to the bezel and to the movable lens cap.

[0118] The membrane 15 of the embodiments shown in Figures 2 to 30 functions as a biasing member or structure to bias the movable lens cap 13 into a ‘home’ position (shown in Figures 5 and 6 in particular) away from the chassis 12, and against the constraint of the bezel 14 by abutting an underside of the bezel 14.

[0119] The button assembly 10 is a mechanical button in which the movable lens cap 13 functions as a depressible button member which is movable relative to the chassis 12.

[0120] As shown in Figure 6, the button assembly 10 may be positioned relative to a planar substrate 11. The substrate 11 may be formed from any material including particularly plastic, glass or metal.

[0121] The button assembly 10 may be provided above a display 16 with at least a portion of the display 16 viewable through the lens cap 13 and / or other parts of the button assembly 10. The display may be of any type. The display may be static ordynamic. The display may comprise an electronic display screen. This may provide the ability to quickly and easily adjust the information displayed thereon. The electronic display screen may for example be an LED or LCD display screen as shown in Figure 6. If the display is static, the display may comprise artwork to be viewed through the lens cap and / or other parts of the button assembly.

[0122] In the illustrated embodiments, the button assembly 10 is fixed to the substrate 11 through an aperture formed in the substrate 11. One or more components or parts of components may be received at least partially into or through the aperture in the substrate 11.

[0123] The movable lens cap 13 is preferably a floating component provided relative to and depressible relative to the chassis 12.

[0124] A number of alignment pins 50 are provided, mounted on the chassis 12 and received through aligned openings on the PCB layer 17 and the lens cap 13 or membrane 15 to align the components of the button assembly 10.

[0125] As shown in Figure 5, a PCB control layer 17 may be provided in the button assembly 10. The at least one sensor 18 may be provided to monitor the position of the lens cap 13 to determine if the lens cap 13 has been pressed or not. The embodiment illustrated in Figures 6 to 12 is a contact sensor configuration whereas the embodiment illustrated in Figures 13 to 16 is an IR sensor configuration.

[0126] The chassis 12 of the button assembly illustrated includes a body mounted to the substrate through the aperture in the substrate. At least a portion of the chassis 12 is dimensioned relative to the dimension of the aperture to limit and preferably prevent lateral movement of the chassis 12, and thereby the button assembly 10, relative to the substrate 11. The chassis 12 allows the lens cap 13 to be depressed only, substantially preventing any lateral movement of the movable lens cap 13.

[0127] The chassis 12 may have any shape, but as shown in Figure 5, may be generally annular about a central opening 19 through the chassis 12 when viewed in plan, although as shown, the chassis 12 is not required to be circular.

[0128] The chassis 12 may comprise a lower, substantially tubular portion 21 to be received within the aperture in the substrate 11 with the central opening 19 definedthrough the tubular portion. A circumferential shoulder 20 may extend radially from the tubular portion 21. An underside of the circumferential shoulder 20 will preferably abut an upper side a top gasket 22 provided between the circumferential shoulder 20 and the upper surface of the substrate 11.

[0129] In the illustrated embodiments, a gutter 23 is provided radially inside the substantially tubular portion 21. The gutter 23 shown extends substantially continuously about the chassis 12. When the button assembly 10 is mounted relative to the substrate lias shown in Figure 6, the gutter 23 is received at least partially within the aperture in the substrate 11. The gutter 23 includes an outer wall 24 of the substantially tubular portion 21, and an inner wall 25 spaced radially inwardly from the outer wall 24. As shown in Figure 6, the inner wall 25 defines the central opening 19 through the chassis 12. The circumferential shoulder 20 is provided at an upper end of the outer wall 25, extending radially outwardly therefrom. The inner wall 24 and outer wall 25 are shown substantially parallel to one another. A lower, linking wall extends between lower portions of the inner wall 24 and outer wall 25 to form the gutter 23.

[0130] In the illustrated form, the control layer 17 is located within the gutter 23, as is the at least one sensor 18.

[0131] A lower gasket 26 is provided between a lower side of the chassis 12 and the display 16 to seal against the display 16.

[0132] As shown in Figure 7, the circumferential shoulder 20 has an upstand provided thereon to allow attachment of the bezel 14 relative thereto.

[0133] As shown in Figure 6, the movable lens cap 13 may preferably span or cover the central opening 19 provided in the chassis 12. The movable lens cap 13 shown includes a transverse portion 28 to extend across the central opening 19 in the chassis 12, preferably to a location outside the inner wall 25 of the chassis 12. The transverse portion 28 is shaped to correspond to the shape of the central opening 19 but be larger in dimension. One or more depending side wall portions 29 are provided at the periphery of the transverse portion 28. In the illustrated form, a single depending side wall portion 28 is provided extending completely about the periphery of the transverse portion 28. As shown in Figures 6 and 7, the one or more depending side wall portions29 depend outside the inner wall 25 of the chassis 12. This configuration will preferably minimise or limit lateral movement of the lens cap 13 on the chassis 12.

[0134] A radially extending portion 30 is provided at a lower end of the one or more depending side wall portions 29. The radially extending portion 30 extend radially outwardly therefrom. The radial extending portion 30 abut an underside of a part of the bezel 14 when the lens cap 13 is in the home position. In some embodiments however such as that shown in Figure 13 and 14, a portion of the membrane 15 may be interposed between the upper side of the radially extending portion 30 of the lens cap 13 and the underside of the bezel 14.

[0135] As mentioned above, the lens cap 13 is preferably provided in a floating configuration relative to the chassis 12. The lens cap 13 is preferably mounted to the bezel, via the membrane 15 and is in turn, mounted relative to the chassis 12. The membrane 15 may bias the lens cap 13 away from the chassis 12.

[0136] The lens cap 13 may be transparent, partially transparent, partially opaque, or opaque.

[0137] An inner end of the membrane 15 attaches to the radially extending portion 30 of the lens cap 13. In the embodiment shown in Figures 6 to 12, the membrane 15 attaches to an underside of the radially extending portion 30 of the lens cap 13. In the embodiment shown in Figures 13 to 16, the membrane 15 attaches to an upper side of the radially extending portion 30 of the lens cap 13.

[0138] The membrane 15 may be bonded or co-moulded with the radially extending portion 30 of the lens cap 13.

[0139] In the contact sensor embodiment shown in Figures 6 to 12, a contact or pressure pad 31 is provided on an underside of the membrane 15 at an inner end of the membrane 15.

[0140] The particular configuration of the radially extending portion 30 may be dependent upon the particular type of sensor configuration which is used to detect movement of the lens cap 13. For example, in a physical or electrical contact embodiment such as that shown in Figures 6 to 12, the membrane 15 may attach to an underside of the radially extending portion 30 and in this case, the radially extendingportion 30 may have an inverted U-shaped configuration (downwardly facing), whereas in an infrared (IR) sensor embodiment such as that shown in Figures 13 to 16, the membrane 13 may attach to an upper side of the radially extending portion 30 and in this case, the radially extending portion 30 may have U-shaped configuration (upwardly facing).

[0141] As shown, the u-shaped configuration may be formed from an inner wall and outer wall with a depression or channel between the inner wall and outer wall.

[0142] In the IR sensor embodiment, a reflective portion or surface 32 may be provided on an underside of the radially extending portion 30 of the lens cap 13 to reflect radiation to the infrared transmitter / receiver 33. The reflective portion or surface 32 is optically reflective or reflect another type of signal but will preferably depend upon the nature of the sensor used.

[0143] The lens cap 13 may be provided in a unitary or single piece configuration. The lens cap 13 may be moulded in a single piece.

[0144] As shown, the bezel 14 includes a radially inwardly extending portion which extends over an outer portion of the lens cap 13 to constrain movement of the lens cap 13 away from the chassis 12.

[0145] As shown in Figures 7 and 14 in particular, an inner end of the radially inwardly extending portion of the bezel 14 may be spaced from and adjacent part of the lens cap 13 when the bezel 14 is attached to the chassis 12. This may provide clearance between the bezel 14 and the lens cap 13. This may also provide an entry / exit opening 34 between the bezel 14 and the lens cap 13.

[0146] As mentioned above, in the illustrated embodiments, the membrane 15 attaches to the bezel 14. The membrane 15 attaches to the bezel 14 at an outer side of the bezel 14, and as shown, preferably attaches to an underside of the bezel 14.

[0147] Again, any attachment mechanism may be used. For example, the bezel 14 and membrane 15 may be co-moulded or bonded together. Preferably, the bezel 14 and membrane 15 are attached in a watertight and / or dust- tight configuration.In the illustrated embodiment, a shaped depression is provided in the bezel 14 to receive a correspondingly shaped portion of the membrane 15 to strengthen the attachment between the bezel 14 and membrane 15.

[0148] As shown, an outer end of the membrane 15 may be provided with an enlarged end portion to facilitate attachment between the bezel 14 and the membrane 15 and an inner end of the membrane 15 may be provided with an enlarged end portion to facilitate attachment between the lens cap 13 and the membrane 15.

[0149] One or more sensors 18 may be provided to sense movement of the lens cap 13 to determine when the lens cap 13 has been depressed. Any number of sensors may be provided. Any type of sensor may be provided. A combination of sensors may be provided in some embodiments.

[0150] As mentioned above, the one or more sensors may be provided in the gutter 23 in the chassis 12. The membrane 15 is preferably located above the gutter 23, extending across the gutter 23 from the bezel 14 to the lens cap 13. This will act to protect any one or more sensor provided in the gutter 23 and / or any other components such as the controller.

[0151] The sensor may detect depression. The sensor may be binary, detecting a press and release, such as a physical touch making electrical contacts or a more complex sensor may be used such as proximity sensing measuring distance, depth and / or period of depression.

[0152] The membrane 15 of the illustrated embodiment is flexible and resilient. A silicon material may be particularly preferred. The membrane 15 is also preferably waterproof and / or particle proof. Preferably, the membrane 15 may have an ingress protection rating of IP 65 or higher.

[0153] The membrane 15 may have shape memory in order to bias the movable lens cap 13 into a home position, abutting the bezel 14 once the lens cap 13 is pressed and released.

[0154] As mentioned above, the inner end and / or outer end of the membrane 15 may be shaped or be provided with an engagement formation to engage with a part of the lens cap 13 and / or bezel 14 more securely. The central portion of the membrane 15 maypreferably be substantially planar, although as mentioned above, may be shaped (and / or have shape memory) to allow deformation of the membrane 15 as the lens cap 13 is pressed and released.

[0155] The membrane 13 may preferably be substantially annular in overall shape when viewed in plan with a central opening within which the lens cap 13 is provided, however it is not essential that the membrane 15 be circular as the shape of the membrane 15 may preferably be dependent upon the shape of the lens cap 13 and / or bezel 14.

[0156] The membrane 15 is bonded or co-moulded with the lens cap 13 and / or bezel 14 at the locations shown in Figures 8, 9 and 18 by the dashed lines and / or dashed arrows.

[0157] When attached to the lens cap 13 and bezel 14, the membrane 15 will preferably extend radially between the lens cap 13 and bezel 14 to form a cavity 36 above the lens cap 13 / membrane 15 / bezel 14 as shown in Figures 9, 11, 18 and 20 and to prevent liquid and / or particulate matter entering the button assembly 10 below the lens cap 13 / membrane 15 / bezel 14.

[0158] As shown in Figures 10, 11, 19 and 20, any liquid spilled on the button may collect at the entry / exit opening 34 and enter the cavity 36. The cavity may contain any liquid as shown in Figures 11 and 20. This may prevents liquid from entering the lower part of the button, beneath the lens cap 13 / membrane 15 / bezel 14.

[0159] The lens cap 13 and bezel 14 are preferably liquid and / or particle proof, preferably to the same or greater degree as the membrane 15.

[0160] Due to the configuration of the lens cap 13 / membrane 15 / bezel 14, liquid cannot enter the lower part 37 of the button assembly 10 where more sensitive working components are located. When the lens cap 13 is pressed, the opening 34 between the lens cap 13 and the bezel 14 opens, which may allow liquid to enter, but the cavity 36 defined by the lens cap 13, membrane 15 and bezel 14 contains the liquid above any working components of the button assembly 10. This liquid cannot enter the lower part of the button. Due to the nature of the membrane 15 and the floating lens cap 13, even sticky liquids may not affect the button movement and / or function, unlike a traditionalbutton which requires guiding frictional parts, which are adversely affected by ingress and sticky liquids. Any liquid which does not enter the cavity, will preferably simply flow off the button assembly as shown in Figure 12.

[0161] In use, if the lens cap 13 is pressed repeatedly and preferably quickly, then any liquid in the cavity 36 will be ejected from the cavity 36, with the membrane 15 functioning as a positive displacement pump. This provides a self-cleaning function when operating the button assembly.

[0162] With the design of the button assembly 10, even if the liquid in the cavity 36 above the membrane 15 is very sticky (or has dried) and doesn’t self-eject, then the design of the button assembly 10 allows for a cleaning fluid / spray or water to be poured into the cavity 36 and then by pressing and releasing the lens cap 15 multiple times, material is ejected through the entryway 34. Any remaining (now) clean water will evaporate or remain in the cavity 36 above the membrane without effecting operation of the button assembly 10.

[0163] The button assembly shown in Figures 21 to 23 includes an optical block 35 to present an image or display optimally to a user. For example, an image of the display may be lifted using an optical block (bringing image to or closer to the surface of the lens cap) as shown in Figure 21 or an optical refraction block (which gives the appearance of lift depending on the angles viewed) as shown in Figure 22. Both methods may also make the inside edge of the button appear shallower, giving the impression that the button is shallower as shown in Figure 23, or the image is higher.

[0164] The optical block 35 may have any shape but may correspond to the shape of an underside of the lens cap 13 and / or central opening 19 in the chassis 12. The optic block may be mounted within the central opening 19 in the chassis 12, beneath the lens cap 13. The optical block 35 may be fixed relative to the lens cap 13 or may move with the lens cap 13. In the illustrated embodiments, the optical block 35 is closely received within the lens cap 13 and is fixed relative to the display, with the lens cap 13 moving above the optical block 35.

[0165] The button assembly 10 may comprise a halo illumination configuration, preferably on or associated with the periphery of the button assembly 10. The haloillumination may comprise at least one light source 37 within the button assembly and a pathway to an at least partially transparent escape window 38 for the light to leave the button assembly 10.

[0166] The at least partially transparent escape window 38 may be provided continuously about the button assembly 10. As shown in Figures 24 and 25, the at least partially transparent escape window 38 may be provided below the bezel 14, preferably between the bezel 14 and the substrate 11.

[0167] The at least one light source 37 may be or comprise an LED. The at least one light source 37 may be provided within the gutter 23, preferably on or associated with the PCB 17.

[0168] As shown in Figure 24, the lower linking wall of the gutter 23 and / or the at least one light source 37 may not be at the same level and / or orientation as the at least partially transparent escape window 38. If the light source 37 has a wide throw 39 as shown in Figure 24, the positioning of the light source 37 may result in a smaller than desired percentage of light 40 emitted by the at least one light source 37 being directed towards the at least partially transparent escape window 38.

[0169] To address this problem, the button assembly shown in Figure 25 comprises a light pipe 41 and / or diffuser to guide the light emitted to the at least partially transparent escape window 38 of the button assembly. As shown in Figure 25, this may make the halo effect more prominent and / or more efficient in terms of light emitted being directed to the at least partially transparent escape window 38.

[0170] The light pipe may be shaped. The light pipe 41 may be located at least partially within the gutter 23 as shown in Figure 25 which shows the light pipe provided about the light source 37. The light pipe 41 may function to direct the light only, or the light pipe may direct and diffuse the light. A light pipe 41 may be used to diffuse the light with the aid of geometric features, surface finishes and / or material selection. For example, an additive such as a slightly opal white colour additive may be added into the material used to construct the light pipe 41.

[0171] Due to the compactness of the button assembly 10, the at least one light source 37 may be located close to the at least partially transparent escape window 38. This cancreate a problem illustrated in Figure 26, where the light does not have sufficient distance to disperse and / or mix. The result of this can be a hotspot 42 effect with ‘dead’ spots 43 where there is little or no light exiting the at least partially transparent escape window 38.

[0172] To compensate for this, more light sources 37 can be provided, therefor reducing the pitch and distance between the light sources 37. This is a more costly solution for the hotspot effect.

[0173] Another solution for the hotspot effect is shown in Figure 27, to use light sources 37 with a wider dispersion angle which closes or fills the ‘dead’ spots 43.

[0174] As mentioned above, the light pipe 41 may also function as a diffuser to increase the mixing of light effect. Use of a diffusing light pipe such as that shown in Figure 28 may distribute the light exiting the button assembly 10 through the at least partially transparent escape window 38 more evenly, despite the close proximity the light source 37 may have to the at least partially transparent escape window 38. The diffusion may be created internally 45 within the material of the light pipe 41, or a surface configuration 44 may be provided as shown in Figure 28 to diffuse and distribute the light 46.

[0175] Another possible issue in a button assembly 10 is shown in Figure 29. In this button assembly, the at least one light source 37 illuminates surfaces 47 of the internal parts of the button assembly 10 and makes internal parts of the button visible through the lens cap 13, potentially through a wide viewing angle 48. To minimise or avoid this, an upper surface 49 of the light pipe 41 may be masked with an opaque (light blocking) surface, coating or effect. This opaque (light blocking) surface, coating or effect may be sprayed, masked with a covering film or component, dual moulded, or the like. The opaque (light blocking) surface, coating or effect may be black, chrome or any other colour provided that it does not transmit light through it. This may direct the light and mask the light from illuminating internal surfaces of the button assembly 10.

[0176] The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.

Claims

CLAIMS1. A button assembly for a substrate, the button assembly comprising:a. a chassis mounted to the substrate through an aperture in the substrate; b. a movable lens cap mounted for movement relative to the chassis; c. a bezel mounted to the chassis to constrain movement of the movable lens cap away from the chassis;d. one or more sensors operable to sense the movable lens cap; and e. a membrane attached to the bezel and to the movable lens cap.

2. A button assembly as claimed in claim 1 wherein the membrane is flexible and resilient to bias the movable lens cap back into a home position, away from the chassis, and / or against the constraint of the bezel after the movable lens cap is depressed and released.

3. A button assembly as claimed in claim 1 or claim 2 further comprising a controller provided in the button assembly associated with the at least one sensor to monitor the position of the lens cap to determine if the lens cap has been pressed or not.

4. A button assembly as claimed in any one of the preceding claims wherein the chassis is annular having a tubular body, a radially outwardly extending circumferential shoulder and a central opening through the chassis and the movable lens cap is mounted over an upper end of the central opening.

5. A button assembly as claimed in claim 4 further comprising a gutter radially inside the substantially tubular portion and the at least one sensor is located within the gutter.

6. A button assembly as claimed in claim 4 or claim 5 wherein the movable lens cap comprises a transverse portion to extend across the central opening in the chassis and one or more depending side wall portions provided at the periphery of the transverse portion to mount the movable lens cap over the upper end of the central opening.

7. A button assembly as claimed in claim 6 further comprising a radially outwardly extending portion provided relative to the one or more depending side wall portions and an inner end of the membrane is mounted to the one or more depending side wall portions and / or to the radially outwardly extending portion.

8. A button assembly as claimed in claim 6 or claim 7 wherein the membrane is mounted to the bezel at an outer end of the membrane.

9. A button assembly as claimed in claim 7 or claim 8 wherein the membrane is bonded or co-moulded with the side wall portions and / or radially extending portion of the lens cap and / or bezel.

10. A button assembly as claimed in any one of the preceding claims wherein the movable lens cap is transparent, partially transparent, partially opaque, or opaque.

11. A button assembly as claimed in any one of the preceding claims wherein the bezel comprises a radially inwardly extending portion which extends over an outer portion of the movable lens cap to constrain movement of the movable lens cap away from the body and an inner end of the radially inwardly extending portion of the bezel is spaced from an adjacent part of the lens cap when the bezel is attached to the chassis.

12. A button assembly as claimed in any one of the preceding claims wherein the membrane is annular in overall shape when viewed in plan with a central opening about the movable lens cap.

13. A button assembly as claimed in any one of the preceding claims wherein the membrane extends radially between the movable lens cap and bezel to form a cavity above the movable lens cap and membrane and bezel.

14. A button assembly as claimed in any one of the preceding claims wherein the movable lens cap and bezel are liquid and / or particle proof to at least the same degree as the membrane.

15. A button assembly as claimed in any one of the preceding claims further comprising an optic block to lift an image or display to or closer to an upper surface of the movable lens cap.

16. A button assembly as claimed in any one of the preceding claims further comprising an optic block to give an appearance of lifting an image or display to or closer to an upper surface of the movable lens cap depending on a viewing angle by refraction.

17. A button assembly as claimed in claim 15 or claim 16 wherein the optic block is shaped to correspond to the shape of an underside of the movable lens cap.

18. A button assembly as claimed in any one of the preceding claims further comprising a halo illumination configuration, on or associated with the periphery of the button assembly, the halo illumination comprising at least one light source within the button assembly and a pathway to an at least partially transparent escape window for the light to leave the button assembly.

19. A button assembly as claimed in claim 18 wherein the at least partially transparent escape window is provided continuously about the button assembly.

20. A button assembly as claimed in claim 18 or claim 19 wherein the at least partially transparent escape window is provided between the bezel and the substrate.

21. A button assembly as claimed in any one of claims 18 to 20 further comprising a light pipe to direct light from the at least one light source to an at least partially transparent escape window.

22. A button assembly as claimed in claim 21 wherein an upper surface of the light pipe is masked with an opaque surface, coating or effect.

23. A button assembly as claimed in any one of claims 18 to 22 further comprising a diffuser to scatter light from the at least one light source to the at least partially transparent escape window.

24. A button system comprising a button assembly as claimed in any one of the preceding claims mounted to the substrate through an aperture formed in thesubstrate and provided above a display with at least a portion of the display viewable through the lens cap and / or other parts of the button assembly.

25. A button system as claimed in claim 24 comprising the optic block defined in any one of claims 15 to 17 mounted below the movable lens cap with the movable lens cap depressible above the optic block.

Images