Illuminated knob assembly for an appliance

A knob assembly includes a light guide and a control knob that is independently rotatable relative to the light guide. The light guide is positioned at an aperture formed on a surface such that the light guide receives light emitted by a light source positioned below the surface along a vertical direction. The light guide also defines a guide opening, and further includes an opaque and translucent region. The control knob defines a light opening and is rotatably coupled to a stem extending through the guide opening. The control knob is rotatable between a first and second position. In the first position, the light opening is positioned entirely over the opaque region of the light guide along the vertical direction. In the second position, the light opening is positioned entirely over the translucent region of the light guide along the vertical direction. A related cooktop appliance is provided.

FIELD OF THE INVENTION

The present subject matter relates generally to control knobs on an appliance, such as a cooking appliance. More particularly, the present subject matter relates to an improved assembly for illuminating the control knobs such that light may be used to provide indicia regarding movement or position of the control knobs.

BACKGROUND

Knobs are commonly used on a variety of commercial and residential appliances to control an operating condition of the appliance. Knobs are particularly common on cooking appliances, such as stoves or cooktops. Various shapes and sizes can be used depending upon e.g., the intended application, aesthetics, and other factors.

For example, cooktop traditionally have at least one heating element positioned at a cooktop surface for use in heating or cooking an object, such as a cooking utensil, and its contents. The at least one heating element may heat a cooking utensil directly through induction heating, or may use another heat source such as electrically resistant coils or gas burners. In gas burner cooktops, air is required for the combustion of the gas fuel. For that reason, some gas burner cooktops have air intake openings to allow for a sufficient amount of air intake to meet the combustion requirements of the gas burners. These openings are sometimes located beneath the knobs. When this is the case, some gas cooktops have light installed below air intake openings located underneath the knobs so that the light may shine through the openings and communicate certain conditions to the user, such as e.g., whether the knob is in an “on” position.

Certain challenges exist with this construction, however. Such construction, for example, does not use light emitted through the openings to communicate rotation of the control knob. As such, this construction cannot rely upon light to provide indicia regarding movement or position of the control knob.

Accordingly, an improved control knob assembly that uses light to indicate movement and position of the control knob would be beneficial.

BRIEF DESCRIPTION OF THE INVENTION

In a first exemplary embodiment, a knob assembly for a cooking appliance is provided. The knob assembly may generally include a surface defining an aperture. The knob assembly may also include a light guide positioned at the aperture, wherein the light guide may define a guide opening and may further include an opaque region and a translucent region. In addition, the knob assembly may include a light source located below the surface along a vertical direction, wherein the light source is positioned such that light emitted by the light source is received by the light guide. The knob assembly may also include a control knob rotatably coupled to a stem extending through the guide opening of the light guide. The control knob may include a light opening and may be rotated between a first and second position. In the first position, the light opening may be positioned entirely over the opaque region of the light guide. The control knob may be rotated to the second position such that the light opening may be positioned entirely over the translucent region of the light guide.

In a second exemplary embodiment, a cooktop appliance is provided. The cooktop appliance may generally include a cooktop surface defining an aperture. The cooktop appliance may also include a burner disposed in the cooktop surface. In addition, the cooktop appliance may include a knob assembly. The knob assembly may generally include a surface defining an aperture. The knob assembly may also include a light guide positioned at the aperture, wherein the light guide may define a guide opening and may further include an opaque region and a translucent region. In addition, the knob assembly may include a light source located below the surface along a vertical direction, wherein the light source is positioned such that light emitted by the light source is received by the light guide. The knob assembly may also include a control knob rotatably coupled to a stem extending through the guide opening of the light guide. The control knob may include a light opening and may be rotated between a first and second position. In the first position, the light opening may be positioned entirely over the opaque region of the light guide. The control knob may be rotated to the second position such that the light opening may be positioned entirely over the translucent region of the light guide.

DETAILED DESCRIPTION

Referring now to the drawings,FIG. 1illustrates an exemplary embodiment of a cooking appliance10of the present disclosure. Cooking appliance10may be, e.g., fitted integrally with a surface of a kitchen counter, or be a part of one or more oven appliances. Cooking appliance10can include a chassis (not shown) and a cooktop surface12having one or more heating elements14for use in, e.g., heating or cooking. In one exemplary embodiment, cooktop surface12is comprised of ceramic glass. In other embodiments, however, cooktop surface12may be comprised of another suitable material, such as a metallic material (e.g., steel) or other suitable non-metallic material. Heating elements14may be various sizes, as shown inFIG. 1, and may employ any suitable method for heating or cooking an object, such as a cooking utensil (not shown), and its contents. In one embodiment, for example, heating element uses a heat transfer method, such as electric coils or gas burners, to heat the cooking utensil. In another embodiment, however, heating element14uses an induction heating method to heat the cooking utensil directly.

The amount of heat delivered by each heating element14on cooktop surface12is controlled by a corresponding controller36and control knob16, as is detailed in the exemplary embodiments described below and shown inFIG. 2. Knob16, as used herein, refers to any configuration of dial, and not just one having a circular base, as shown inFIG. 1. For example, the present disclosure contemplates exemplary embodiments wherein knobs16have a rectangular base, an ovular base, or any other shape having one or more curved lines, straight lines, or both.

FIG. 2shows an exploded perspective view of an exemplary embodiment of a knob assembly8for a cooking appliance10. In this embodiment, knob assembly8includes cooktop surface12defining an aperture13. Cooktop surface12, as used herein, refers to any surface of cooking appliance10. For example, the present disclosure contemplates exemplary embodiments where the entirety of cooktop surface12is comprised of a single suitable material and other embodiments where cooktop surface12is comprised of one material proximate to heating elements14, and another material proximate to control knobs16.

In one exemplary embodiment, knob assembly8also includes a light guide40positioned at aperture13in cooktop surface12. Light guide40may include an upper portion50and a lower portion60. Upper portion50is positioned above and spaced apart from lower portion60along a vertical direction V. Further, upper portion50defines a guide opening51. Light guide40receives light emitted by a light source15of knob assembly8that, as shown inFIG. 3, may be positioned below cooktop surface12along vertical direction V. Light source15may be a light-emitting diode (LED) or other suitable source. In some embodiments, light source15may be positioned collinear with aperture13along vertical direction V.

In the embodiment shown, control knob16of knob assembly8includes a top surface17that defines a light opening18. Control knob16also includes a side surface19that extends downward from top surface17along vertical direction V. In the embodiment shown, control knob16is rotatably coupled to a stem34extending through aperture13and guide opening51along vertical direction V. More specifically, stem34extends from a controller36, such as a controller used to adjust the amount of heat delivered to heating element14. Further, control knob16is independently rotatable, such as about vertical axis V relative to light guide40.

AlthoughFIG. 2depicts stem34and controller36as a single component, one of ordinary skill in the art understands that other embodiments in which stem34is a separate component from controller36. For instance, stem34may, in one embodiment, be integrally formed with control knob16. In yet another embodiment, stem34may be removably coupled to both control knob16and controller36.

Still referring to the embodiment shown inFIG. 2, controller36may include a memory and microprocessor, such as a general or special purpose microprocessor operable to execute programming instructions or micro-control code. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor. Alternatively, controller36may be constructed without using a microprocessor, e.g., using a combination of discrete analog and/or digital logic circuitry (such as switches, amplifiers, integrators, comparators, flip-flops, AND gates, and the like) to perform control functionality instead of relying upon software.

In the embodiment shown, knob assembly8includes a lens20positioned between top surface17of control knob16and light guide40along vertical direction V. Lens20includes a raised portion22that extends into light opening18along vertical direction V. In some exemplary embodiments, a top surface24of raised portion22is substantially flush with top surface17of control knob16. In other embodiments, however, top surface24of raised portion22may extend above top surface17of control knob16along vertical direction V. Lens20, including raised portion22, may be made from any suitable material, such as glass or plastic.

Knob assembly8may also include a bezel90positioned between upper portion50of light guide40and cooktop surface12along vertical direction V. Bezel90may be made from any suitable material, including metals and plastics.

Referring now toFIGS. 4-6, an exemplary embodiment of light guide40is shown. In this exemplary embodiment, upper portion50of light guide40includes a top surface52having an opaque region54and a translucent region56. Opaque region54is comprised of an opaque material suitable to block light received from light source15. In contrast, translucent region56is comprised of a translucent material that allows light from light source15to pass therethrough. Further, although in the embodiment shown, opaque region54and translucent region56comprise equal amounts of top surface52, one of ordinary skill in the art having the benefit of the present disclosure would understand that opaque region54and translucent region56may comprise disproportionate amounts of top surface52.

Still referring toFIGS. 4-6, upper portion50of light guide40also includes a side surface58that extends downwardly from top surface52along vertical direction V. Further, upper portion50of light guide40includes a flange59that extends outward from side surface58along a radial direction R, and is positioned between bezel90and control knob16along the vertical direction V. In the embodiment shown, flange59extends around a perimeter of side surface58. In alternative embodiments, however, flange59may only extend around a portion of the perimeter of side surface58. Still further, flange59and side surface58may be comprised of translucent material such that flange59and side surface58may, upon receiving light from light source15, illuminate the perimeter of side surface58.

Lower portion60of light guide40is positioned at aperture13of cooktop surface12, and defines a first aperture60and a second aperture62. In this embodiment, lower portion60may be fastened to cooktop surface12with mechanical fasteners (not shown) extending through first and second aperture62,64and corresponding apertures (not shown) in cooktop surface12. In other embodiments, lower portion60of light guide40may not include first and second apertures62,64and may, instead, be coupled to cooktop surface12via any suitable bonding material.

Light guide40also includes a plurality of support members70extending from upper portion50to lower portion60. Each support member70is preferably comprised of translucent material. Further, in the embodiment shown, upper portion50and lower portion60are both circular and, as a result, both upper and lower portions50,60define a circular cross-sectional area. More specifically, upper portion50of light guide40defines a first maximum diameter DUthat surrounds a second maximum diameter DLdefined by lower portion60of light guide40. As such, each support member70extends radially inward from upper portion50of light guide40to lower portion60of light guide40along radial direction R.

Referring now toFIGS. 2, 3, 4 and 7, control knob16is shown in a first position710in which light opening18of control knob16is positioned entirely over opaque region54of light guide40along vertical direction V. As such, since, in first position710, light opening18is positioned entirely over opaque region54, light emitted by light source15cannot illuminate light opening18. In some embodiments, first position710may correspond to an “off” position in which a heating element14controlled by control knob16via controller36delivers no heat.

Control knob16is rotatable from first position710shown inFIG. 7to other positions described below in more detail. Further, since control knob16is independently rotatable relative to light guide40, position of light opening18relative to top surface52of light guide40may vary as control knob16rotates. More specifically, position of light opening18relative to top surface52of light guide40may vary such that light opening18is no longer positioned entirely over opaque region54along vertical direction V.

Referring now toFIGS. 2, 3, 4 and 9, control knob16is shown in a second position910in which light opening18of control knob16is positioned entirely over translucent region56of light guide40along vertical direction V. As such, since, in second position910, light opening18is positioned entirely over translucent region56, light emitted by light source15illuminates light opening18. In some embodiments, second position910may correspond to a “fully on” position in which heating element14controlled by control knob16via controller36delivers a maximum amount of heat.

Still further, as shown inFIG. 8, control knob16is rotatable to an intermediate third position810in which a first portion820of light opening18is positioned over opaque region56along vertical direction V, and a second portion840of light opening18is positioned over translucent region56along vertical direction V. Intermediate third position810may be encountered during rotation of control knob16between first position710and second position910. As such, since, in intermediate third position810, only second portion840of light opening18is positioned over translucent region56, light emitted by light source15illuminates only second portion840of light opening18. In some embodiments, intermediate third position810may correspond to an “partially on” position in which heating element14controlled by control knob16via controller36delivers an amount of heat that is less than the maximum amount of heat that corresponds to the “fully on” position discussed above.

AlthoughFIG. 8shows intermediate third position810as being halfway between first and second positions710and910, it is understood that intermediate third position810may correspond to any number of intermediate third positions between first and second positions710and910. As an example, control knob16may be rotated to an intermediate third position810in which seventy-five percent of light opening18is positioned over translucent region56along vertical direction V, and the remaining twenty-five percent of light opening18is positioned over opaque region54.

Referring now toFIG. 10, another exemplary embodiment of light guide40is shown. In this embodiment, light guide40includes a shaft80that extends from lower portion60through aperture13along vertical direction V. Further, light source15is positioned orthogonal to vertical direction V such that light emitted by light source15is received by light guide40via an outer surface of shaft80.