Patent Description:
Switch panels for vehicles, particularly in the aviation industry, include push buttons, knobs, switches, etc. that must provide several functions in a limited amount of space. In particular, the buttons must provide an electrical contact with a corresponding contact on the panel when pressed, and the buttons must also convey information to the user via tactile feedback and/or backlit illumination of the buttons via incandescent lamps. Typically, light from the incandescent lamps is distributed to the buttons via a light-pipe. To accommodate the light sources, light-pipe, and other components needed for the switch panel, traditional switch panels are generally thick and have a high profile. As used herein, a "high profile" switch panel has a thicknesses of <NUM> or greater. Such switch panels are bulky for areas of limited space (such as aircraft cockpits) and have increased weights that may be limiting to weight-sensitive vehicles such as aircraft.

<CIT> discloses a backlighted, full travel, sealed keyboard. A translucent membrane is disposed between the keys and a printed circuit board and includes a gasket around its perimeter which is sealingly engaged by the housing for the keyboard. Domes for each key are formed integrally with the membrane, so that a liquid tight seal is formed between the keys and the printed circuit board. The keyboard is backlighted with LEDs disposed on the printed circuit board. The domes are configured to allow full travel for each of the keys so that a desired tactile feedback is provided to the user.

According to certain embodiments of the present invention, an aircraft switch panel assembly is provided as set out in claim <NUM>.

In certain embodiments, the aircraft switch panel assembly also includes a back plate, and the cover receiving area is defined between the cover and the back plate. The cover includes a cover outer surface and the back plate includes a back plate outer surface, and a distance from the cover outer surface to the back plate outer surface is a thickness of the aircraft switch panel assembly. In some embodiments, the thickness is less than <NUM>.

In various embodiments, the button assembly includes a button base, a button retainer, and a lens. The button base includes a bottom end, a base side, and a transition portion between the bottom end and the base side, and the transition portion of the button base may be beveled or radiused with a concave or sloped shape. The button retainer may be supported on the button base, and the button assembly may be configured to direct light from below the button base from the at least one light source, through the transition portion, through the button retainer, and through the lens. In certain examples, the bottom end of the button base defines a plunger cavity recessed in the bottom end, and the button retainer includes a ledge within the cover receiving area. The button assembly may also include a plunger at least partially within the plunger cavity and that contacts the switch in the engaged position. In certain cases, the ledge of the button retainer contacts the button stop in the engaged position. In some embodiments, a cavity wall of the plunger cavity extends at an oblique angle relative to the bottom end.

In certain embodiments, the button stop defines a closed perimeter, and the button stop receiving area is within the closed perimeter. In various examples, the button stop is opaque.

In various cases, the switch is within the button stop receiving area.

In various embodiments, the thickness of the switch panel assembly is <NUM>.

In some embodiments, the button base includes a bottom end, a base side, and a transition portion between the bottom end and the base side. In some cases, the transition portion of the button base is beveled or radiused with a concave or sloped shape, and the transition portion may be transparent such that light may pass through the transition portion. The button retainer may be supported on the button base. In various cases, the button assembly is configured to direct light from below the button base, through the transition portion, through the button retainer, and through the lens.

In some embodiments, the bottom end of the button base defines a plunger cavity recessed in the bottom end and the button retainer comprises a ledge. In various cases, the button assembly also includes a plunger cavity recessed in the bottom end. A plunger stem may be within the plunger cavity, and a plunger may be supported on the plunger stem at least partially within the plunger cavity. In various embodiments, a cavity wall of the plunger cavity extends at an oblique angle relative to the bottom end and the cavity wall is opaque. In some examples, the cavity wall is reflective, and the oblique angle is <NUM>°. In certain embodiments, the button assembly also includes at least one intermediate layer between the button base and the lens, and the at least one intermediate layer includes at least one of a diffuser or a filter.

retainer includes a ledge within the cover receiving area. The button assembly may also include a plunger at least partially within the plunger cavity that contacts the switch in the engaged position.

According to certain embodiments of the present invention, a button assembly for a switch panel for an aircraft includes a button base, a button retainer, and a lens. The button base includes a bottom end, a base side, and a transition portion between the bottom end and the base side. In some cases, the transition portion of the button base is beveled or radiused with a concave or sloped shape, and the transition portion may be transparent such that light may pass through the transition portion. The button retainer may be supported on the button base. In various cases, the button assembly is configured to direct light from below the button base, through the transition portion, through the button retainer, and through the lens.

According to certain embodiments of the present invention, a switch panel assembly has a switch panel and at least one button assembly. While the switch panel assembly is discussed for use with aircraft, it is by no means so limited. Rather, embodiments of the switch panel assembly may be used in other types of vehicles or applications as desired.

Referring to <FIG>, in some embodiments, a switch panel assembly <NUM> includes a cover <NUM> and at least one button assembly <NUM>. In the embodiment of <FIG>, the switch panel assembly <NUM> includes six button assemblies <NUM>, however the number of button assemblies <NUM> should not be considered limiting on the disclosure. As illustrated in <FIG>, the switch panel assembly <NUM> may also include a back plate <NUM>, a printed wire board (PWB) <NUM>, at least one button stop <NUM>, at least one light source <NUM>, and/or at least one switch <NUM>. The number, shape, size, and/or arrangement of the cover openings <NUM>, the button assemblies <NUM>, the button stops <NUM>, the light sources <NUM>, and/or the switches <NUM> of the switch panel assembly <NUM> should not be considered limiting on the disclosure.

As best illustrated in <FIG>, <FIG>, and <FIG>, the cover <NUM> includes an outer surface <NUM> and an inner surface <NUM>, and the inner surface <NUM> defines a cover-receiving area <NUM>. As discussed in detail below, various components of the switch panel assembly <NUM>, such as portions of the button assemblies <NUM>, may be housed within the cover-receiving area <NUM>. The cover <NUM> includes at least one cover opening <NUM> that provides access to the cover-receiving area <NUM> and that receives a corresponding button assembly <NUM>. As illustrated in <FIG>, the light sources <NUM>, the button stop <NUM>, and the switch <NUM> for each button assembly <NUM> may be retained within the cover-receiving area <NUM>. The associated button assembly <NUM> may be at least partially within the cover-receiving area <NUM> and the corresponding cover opening <NUM> and may be movable relative to the button stop <NUM> and the cover <NUM>. The cover <NUM> may be formed of materials including but not limited to acrylic, aluminum, stainless steel, aramid fibers, polycarbonate, polypropylene, other metallic materials, other plastic materials, composite materials, or other materials that are able to provide the necessary structural integrity for the switch panel assembly <NUM>.

Referring to <FIG>, the back plate <NUM> includes an outer surface <NUM> that may be a mounting surface of the switch panel assembly <NUM> configured to interface with a vehicle (e.g., aircraft) mounting interface. The back plate <NUM> may be constructed from various suitable dielectric materials as desired, including but not limited to glass epoxy. In other examples, the back plate <NUM> may be constructed from various other materials as desired. In some non-limiting examples, a thickness of the back plate <NUM> is from about <NUM> to about <NUM>, such as about <NUM>, although it need not be in other examples. As best illustrated in <FIG>, the back plate <NUM> and the cover <NUM> may together define the cover-receiving area <NUM> for various components of the switch panel assembly <NUM>.

A distance from the outer surface <NUM> of the cover <NUM> to the outer surface <NUM> of the back plate <NUM> is a thickness <NUM> of the switch panel assembly <NUM>. In certain embodiments, the switch panel assembly <NUM> with the thickness <NUM> is a low profile switch panel assembly <NUM>. As used herein, a "low profile" switch panel assembly has a thickness of less than about <NUM>. In some examples, the thickness <NUM> is from about <NUM> to about <NUM>. In various examples, the thickness <NUM> is of from about <NUM> to about <NUM>. In certain examples, the thickness <NUM> is less than or equal to about <NUM>.

The PWB <NUM> of the switch panel assembly <NUM> may mechanically support and electrically connect the various electrical components of the switch panel assembly <NUM>. As best illustrated in <FIG>, the PWB <NUM> may be provided within the cover-receiving area <NUM>. The PWB <NUM> may be a single layer PWB or a multi-layer PWB as desired. In some non-limiting examples, a thickness of the PWB <NUM> is from about. <NUM> to about <NUM>, such as about <NUM>, although it need not be in other examples. In certain examples, when the back plate <NUM> interfaces with the mounting interface of the vehicle, the back plate <NUM> provides an intermediate dielectric layer between the PWB <NUM> and the mounting interface of the vehicle.

As best illustrated in <FIG>, the button stop <NUM> for a particular cover opening <NUM> is provided within the cover-receiving area <NUM>. In certain aspects, the button stop <NUM> is supported on the PWB <NUM> and has a thickness such that an engagement end <NUM> of the button stop <NUM> is spaced apart from the PWB <NUM>. In various embodiments, a distance between the engagement end <NUM> of the button stop <NUM> and the portion of the inner surface <NUM> of the cover <NUM> adjacent to the cover opening <NUM> is a distance that the button assembly <NUM> may move, and the engagement end <NUM> may selectively engage the button assembly <NUM>. In certain embodiments, the button stop <NUM> is configured to selectively engage a bottom side of the button assembly <NUM> to reduce or prevent over-travel of the button assembly <NUM> and/or damage to the switch <NUM>.

As illustrated in <FIG>, the button stop <NUM> defines a button stop receiving area <NUM>. In certain cases, the button stop <NUM> defines a closed perimeter such that the button stop receiving area <NUM> is completely encircled, although in other embodiments the button stop <NUM> need not define a closed perimeter. The button stop <NUM> may be constructed from various suitable materials as desired, including but not limited to acetal, acrylic, aluminum, stainless steel, aramid fibers, polycarbonate, polypropylene, other metallic materials, other plastic materials, composite materials, or other similar materials as desired. In certain embodiments, the button stop <NUM> may be opaque to minimize or prevent the transmission of light from the light source(s) <NUM> in a direction other than towards the cover opening <NUM>. In certain examples, the button stop <NUM> may have optical distribution properties such that the button stop can assist with light reflection of light emitted from the light source(s) <NUM>.

As best illustrated in <FIG>, each cover opening <NUM> and/or button assembly <NUM> includes at least one associated light source <NUM>, and in certain embodiments, each cover opening <NUM> and/or button assembly <NUM> includes at least two associated light sources <NUM>. As such, the number of light sources <NUM> associated with each cover opening <NUM> and/or button assembly <NUM> should not be considered limiting on the disclosure. In some cases, the light sources <NUM> may be light emitting diodes (LEDs), although in other embodiments, light sources other than LEDs may be utilized as desired. As illustrated in <FIG>, the light sources <NUM> are provided on the PWB <NUM> within the button stop receiving area <NUM> (i.e., the button stop <NUM> surrounds the light sources <NUM>) and are configured to direct light to the button assembly <NUM> of the particular cover opening <NUM>. In embodiments with a plurality of button assemblies <NUM>, each button assembly <NUM> may have one or more dedicated light sources <NUM>.

The switch <NUM> is supported on the PWB <NUM> within the button stop receiving area <NUM> (i.e., the button stop <NUM> surrounds the switch <NUM>) and may be various suitable switch assemblies or other suitable devices that may be engageable with the button assembly <NUM> such that the switch <NUM> is selectively activated or deactivated. In some non-limiting examples, the switch may be an external device (ED) switch that provides tactile feedback to a user. In various embodiments, the switch <NUM> is electrically connected with at least the light sources <NUM> on the switch panel assembly <NUM>. In various embodiments, the switch <NUM> is electrically connected with the light sources <NUM> such that the light sources <NUM> may indicate a status of the switch <NUM>. As some non-limiting examples, the light sources <NUM> may be activated if the switch <NUM> is activated and may be deactivated if the switch <NUM> is deactivated, or the light sources <NUM> may emit a first color or light pattern if the switch <NUM> is activated and may emit a second color or light pattern if the switch <NUM> is deactivated.

Referring to <FIG>, each button assembly <NUM> includes a button base <NUM>, a button retainer <NUM>, a plunger <NUM>, and a lens <NUM>. The button assembly <NUM> may have various suitable shapes or configurations as desired. In some cases, a length of the button assembly <NUM> is less than or equal to about <NUM>, such as about <NUM>, although in other examples, the length may be greater than <NUM> or less than <NUM>.

The button base <NUM> include a base side <NUM> and a bottom end <NUM>. In certain aspects, the base side <NUM> may define a closed perimeter. Optionally, the base side <NUM> is opaque such that light distribution through the base side <NUM> is minimized or prevented. As best illustrated in <FIG>, <FIG>, and <FIG>, the button base <NUM> defines a plunger cavity <NUM> that is recessed relative to the bottom end <NUM>, and the bottom end <NUM> of the button base <NUM> defines an opening <NUM> to the plunger cavity <NUM>. A plunger stem <NUM> may be provided within the plunger cavity <NUM> that may connect with and support the plunger <NUM> such that the plunger <NUM> is at least partially within the plunger cavity <NUM>. In other embodiments, the plunger stem <NUM> may be omitted and the plunger <NUM> may be integrally formed with the button base <NUM> and need not be a separate component. The plunger <NUM> is configured to selectively engage the switch <NUM>. In various examples, the plunger <NUM> at least partially positioned within the plunger cavity <NUM> allows the plunger <NUM> to have a sufficient length such that the button assembly <NUM> can achieve desired switch tactile characteristics and otherwise engage the switch <NUM> as desired. In various examples, a wall <NUM> of the plunger cavity <NUM> may be chamfered and extend at various angles relative to the bottom end <NUM>. In some cases, the wall <NUM> of the plunger cavity <NUM> is angled or chamfered at an angle of about <NUM>°, although various other suitable angles may be utilized. In certain aspects, the angled wall <NUM> of the plunger cavity <NUM> may allow the plunger <NUM> to have normal dynamics during button depression and switch actuation. In some examples, the angled wall <NUM> may include optical distribution features such that the angled wall <NUM> assists in distribution of light from the light sources <NUM>.

As best illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, the button base <NUM> includes a transition portion <NUM> between the bottom end <NUM> and the base side <NUM>. In certain examples, the transition portion <NUM> has a bevel, a concave radius, and/or a concave arcuate shape. The transition portion <NUM> may have a non-linear cross-sectional profile as illustrated in <FIG>, <FIG>, <FIG>, and <FIG>, although in other embodiments, the transition portion may have a linear cross-sectional profile. In various embodiments, the transition portion <NUM> may be clear or transparent such that the transition portion <NUM> may serve as a prism or a lens to further assist in light distribution from the light sources <NUM> through the button assembly <NUM>. In certain aspects, and as best illustrated in <FIG>, the transition portion <NUM> may be proximate to the light sources <NUM> when the switch panel assembly <NUM> is assembled. The transition portion <NUM> may extend completely around the plunger cavity <NUM> or may extend around only a portion of the plunger cavity <NUM> as desired.

As best illustrated in <FIG> and <FIG>, the button retainer <NUM> includes a first end <NUM> and a second end <NUM>, and a distance from the first end <NUM> to the second end <NUM> is a thickness of the button retainer <NUM>. In certain aspects, the first end <NUM> includes a first end opening <NUM>, and the button retainer <NUM> may receive the lens <NUM> in or adjacent to the first end opening <NUM>. When the button assembly <NUM> is assembled with the cover <NUM>, the first end <NUM> may be an outermost portion of the button assembly <NUM>. The second end <NUM> of the button retainer <NUM> includes a second end opening <NUM>, and the second end opening <NUM> may receive the button base <NUM> such that the button retainer <NUM> may positioned on the button base <NUM> with at least a portion of the button base <NUM> received within the button retainer <NUM>. As best illustrated in <FIG> and <FIG>, the button retainer <NUM> includes a ledge <NUM> extending at least partially along a perimeter of the button retainer <NUM>. In some cases, the ledge <NUM> is at the second end <NUM>, although it need not be in other examples. In various embodiments, when the switch panel assembly <NUM> is assembled, the ledge <NUM> is within the cover-receiving area <NUM> between the inner surface <NUM> and the button stop <NUM>. As discussed in detail below, the ledge <NUM> may selectively engage the inner surface <NUM> or the button stop <NUM> depending on a position of the button assembly <NUM> relative to the cover <NUM>. In certain aspects, the button retainer <NUM> may be opaque to minimize or prevent the transmission of light from the light source(s) <NUM> in a direction other than through the first end opening <NUM> or the second end opening <NUM>. In various aspects, the ledge <NUM> overlaps the edges of the cover opening <NUM> to minimize light from escaping through any gap in the switch panel assembly <NUM> between the cover opening <NUM> and the button assembly <NUM>.

The lens <NUM> is supported on the button retainer <NUM> and may at least partially allow light distribution through the button assembly <NUM>. The lens <NUM> may have various finishes as desired such that the lens provides a desired light distribution through the button assembly <NUM>. As some non-limiting examples, the lens <NUM> may be polished, colored, prismatic, diffused (e.g., soda blasted), etc..

Optionally, the button assembly <NUM> may include various intermediate layers <NUM> (filters or other suitable types of layers) between the button base <NUM> and the lens <NUM> that selectively control the light distribution through the button assembly <NUM>. As one non-limiting example, one or more intermediate layers <NUM> may block light distribution through portions of the lens <NUM> such that various text or other visual indicators are visible on the button when the light sources <NUM> are activated. In the embodiment of <FIG>, the button assembly <NUM> includes two intermediate layers <NUM>. <FIG>, <FIG> illustrate some non-limiting examples of various text or visual indicators that might be visible due to the intermediate layers <NUM> and/or the lens <NUM>. Various other suitable types of intermediate layers <NUM> or filters for controlling light distribution through the button assembly <NUM> may be utilized. In other embodiments, the intermediate layers <NUM> may be omitted, and the light distribution through may be controlled by the lens <NUM>.

When the switch panel assembly <NUM> is assembled, the button retainer <NUM> extends partially through the corresponding cover opening <NUM>. Light may be directed from the light sources <NUM>, through the transition portion <NUM> of the button base <NUM> and through the button base <NUM>, optionally through the one or more intermediate layer <NUM>, and through the lens <NUM> out the first end opening <NUM>. The button assembly <NUM> assembled with the switch panel assembly <NUM> may be movable between an engaged position and a disengaged position relative to the switch <NUM>. <FIG> illustrates the button assembly <NUM> in the disengaged position. As illustrated in <FIG>, the ledge <NUM> of the button assembly <NUM> engages the portion of the inner surface <NUM> of the cover <NUM> adjacent to the cover opening <NUM>, and the ledge <NUM> is spaced apart from the button stop <NUM>. In various embodiments, in the disengaged position, the plunger <NUM> is spaced apart from the switch <NUM>. In various embodiments, in the engaged position, the plunger <NUM> of the button assembly <NUM> contacts the switch <NUM>. In various embodiments, in the engaged position, the ledge <NUM> of the button retainer <NUM> engages the button stop <NUM>. However, in certain aspects, the plunger <NUM> may contact the switch <NUM> without the ledge <NUM> engaging the button stop <NUM>, and the ledge <NUM> may engage the button stop <NUM> at a maximum engaged position between the plunger <NUM> and the switch <NUM>. Engagement between the ledge <NUM> and the button stop <NUM> may restrict further movement of the plunger <NUM> away from the cover opening <NUM> and may minimize potential damage to the switch <NUM> due to excessive movement.

The switch panel assembly <NUM> compartmentalizes each button assembly <NUM> with individual light source(s) <NUM>, which may allow the button assemblies <NUM> to be individually controlled, installed, repaired, and replaced as needed and allow for the switch panel assembly <NUM> to be easily adapted as desired. The button stop <NUM> may surround the light sources <NUM> and switch <NUM> for a particular button assembly <NUM>, which may assist in light reflection and prevent over-travel of the button assembly <NUM> and subsequent damage of the switch <NUM>. The recessed plunger cavity <NUM> of the button base <NUM> may ensure that the plunger <NUM> has ample plunger length to achieve desired switch tactile characteristics and use dynamics during button depression and switch actuation. The components of the switch panel assembly <NUM> may also allow the switch panel assembly <NUM> to have the low profile and provide space savings in a vehicle having the switch panel assembly.

<FIG> and <FIG> illustrate another example of a switch panel assembly <NUM> according to various embodiments. The switch panel assembly <NUM> is substantially similar to the switch panel assembly <NUM> except that the switch panel assembly <NUM> has a different shape and includes a single button assembly <NUM>. The switch panel assembly <NUM> also illustrates various wiring <NUM> on the PWB <NUM>, including contacts <NUM> connectable to other components external to the switch panel assembly <NUM>. Compared to the switch panel assembly <NUM>, the button assembly <NUM> of the switch panel assembly <NUM> also omits the intermediate layers <NUM>. Although not illustrated in <FIG> and <FIG>, the switch panel assembly <NUM> may have a back plate similar to the back plate <NUM> in various embodiments.

Claim 1:
An aircraft switch panel assembly (<NUM>) comprising:
a cover (<NUM>) defining a cover receiving area (<NUM>) and a cover opening (<NUM>) providing access to the cover receiving area (<NUM>);
a button stop (<NUM>) within the cover receiving area (<NUM>), wherein the button stop (<NUM>) defines a button stop receiving area (<NUM>) that is aligned with the cover opening (<NUM>);
a switch (<NUM>) within the button stop receiving area (<NUM>);
at least one light source (<NUM>) within the button stop receiving area (<NUM>); and
a button assembly (<NUM>, <NUM>, <NUM>, <NUM>) positioned at least partially in the cover opening (<NUM>) and the cover receiving area (<NUM>), wherein the button assembly (<NUM>, <NUM>, <NUM>, <NUM>) is movable between an engaged position and a disengaged position relative to the switch (<NUM>),
characterised in that
in the engaged position, the button assembly (<NUM>, <NUM>, <NUM>, <NUM>) contacts the button stop (<NUM>) and the switch (<NUM>), and
wherein, in the disengaged position, a ledge (<NUM>) of the button assembly (<NUM>, <NUM>, <NUM>, <NUM>) contacts the cover (<NUM>) and the button assembly (<NUM>, <NUM>, <NUM>, <NUM>) is spaced apart from the button stop (<NUM>) and the switch (<NUM>).