Wall plate insert

A filler element or insert for installation in a decorator-type wall plate when the latter are used to cover mounting boxes containing standard electrical controls, the insert being a substantially rectangular element dimensioned to fit within the central opening in the wall plate. The insert in turn includes an aperture usually centrally disposed therein, the latter aperture being shaped and dimensioned to accommodate the extending or projecting portion of a desired electrical control. The insert also includes means disposed on its edge portion for providing a luminance mask or visual discontinuity between the front surface of the decorator plate and the front surface of the insert. Means are provided for securing the insert in the aperture in the wall plate.

This invention relates to an insert for a wall plate for wall mounted 
electrical controls, receptacles and the like mounted in a wall box. 
Particularly, the present invention is intended for use with the switch 
cover or wall plate of the type shown in STANDARD PUBLICATION NUMBER 
WD1-1979, Page 16, NEMA General Purpose Wiring Devices, National 
Electrical Manufacturers Association, Washington, D.C., generally a 
rectangularly shaped, dished cover approximately 23/4 inches by 41/2 
inches with a central aperture or opening, or multiples of such plate. 
Such a wall plate, commonly referred to as a decorator plate, is 
characterized in having a much larger opening (e.g., 1.31".times.2.63") 
than the standard wall plate, thereby permitting the decorator wall plate 
to be used interchangably for electrical receptacles and for electrical 
control devices such as decorator switches. The prior standard cover or 
wall plate (as distinguished from the decorator plate) used for prior art 
standard switches generally will not properly fit an electrical receptacle 
nor would the standard wall plate for receptacles properly fit switches. 
The large opening in the new decorator wall plate is designed for and fits 
snugly around the new wide decorator switches, duplex receptacles and the 
like. When the decorator plate is installed over other devices such as the 
standard narrow toggle switch, slide dimmer or rotary switch, the 
combination of such device and decorator plate becomes unacceptable 
esthetically, and possibly dangerously exposes a surface of that 
electrical device, which surface should properly be covered. 
Decorator wall switches and matching decorator plates for use therewith are 
currently available in a variety of colors, one of the most common of 
which is white. Because there is no true color standardization among the 
several manufacturers of decorator plates, the shades of color (including 
white) in which the plates are made substantially differ, i.e. the hue may 
be the same but the saturation differs. Inserts used to fill in the 
opening in the decorator plate to surround small projecting portions such 
as the shaft of a rotary electrical control, cannot be expected to match 
the several varieties of white in which the decorator plates are 
available, unless of course a matching insert is provided by the same 
manufacturer and is available to the purchaser. 
Often, a wall box is mounted in a wall so that the plane of the edges of 
the front opening of the box is not flush with the wall surface as is 
should be. Additionally, decorator plates tend to differ in thickness from 
manufacturer to manufacturer if only by some small fractions of an inch. 
An ordinary insert used with the decorator plate is generally supported by 
the switch so that the facing or observable surface of the insert tends to 
be aligned by the orientation of the box. The position of the facing 
surface of the plate, when the latter is installed on the box, is usually 
however determined by the plane of the wall on which the plate rests. 
Consequently, there may be an angular mismatch between the surface of an 
insert and the plate such that one or more edges of the insert lies either 
above or below the corresponding surface of the plate. This mismatch is 
usually also unacceptable esthetically. 
A primary object of the present invention is therefore to provide a filler 
element or insert for installation with decorator plates when the latter 
are used to cover boxes containing standard electrical controls, 
receptacles or the like which have a projecting portion (such as a toggle) 
much smaller than the plate opening, which insert overcomes the 
aforementioned problems. A specific object of the present invention is to 
provide an insert for installation with decorator plates whereby a 
mismatch in color or shade between the insert and the plate is not 
esthetically unacceptable. Another object of the present invention is to 
provide an insert of the type described where mismatches in height between 
the surface of the insert and the surface of the plate are not 
objectionable. The foregoing and other objects of the present invention 
are achieved by providing a rectangular insert which has a thickness equal 
to or greater than the thickness or depth of the plate with which it is to 
be used, the insert itself having at least one aperture dimensioned to 
accomodate the projecting portion of an electrical control or receptacle. 
Means are also provided for securing the insert in position in the plate 
opening. Importantly, means are disposed on the edges of the insert for 
providing a visual discontinuity or luminance mask between the respective 
surfaces of the plate and the insert when the latter is finally positioned 
in the plate opening.

Referring now to FIG. 1, there is shown a decorator wall plate 20 of the 
type hereinbefore described, the wall plate being generally of a 
rectangular configuration with a substantially rectangular aperture or 
opening 22 disposed centrally therein. It will be appreciated that the 
wall plate shown in FIG. 1 is typically of the type which is used with a 
duplex receptacle or a decorator wall witch, but the principles of the 
present invention are equally applicable to other decorator wall plates or 
switch covers which are useful with single receptacles and/or switches or 
electrical controls which are designed to fit. Plate 20 has the usual dual 
mounting screw holes 24 for accomodating screws for mounting the plate on 
a receptacle or control mounted in turn in a wall box. Particularly as 
shown in FIG. 2, when plate 20 is formed of metal sheet or high molecular 
weight polymers, the plate is usually dished so that the edge portions 
thereof are formed with a rounded bevel. Disposed within opening 22 is 
insert 26 formed according to the principles of the present invention. 
Insert 26 is a generally flat element with a substantially rectangular 
shape and is dimensioned to fit snugly within opening 22. Insert 26 also 
defines aperture 28 usually centrally disposed therein, aperture 28 being 
shaped and dimensioned to accomodate the extending or projecting portion 
of a desired or particular electrical control. As shown in FIG. 1 for 
example, aperture 28 is dimensioned to accomodate a standard toggle or 
manually operable lever projecting from a switch. It is understood however 
that aperture 28 may be any particular shape or size according to the 
electrical control to be accomodated. For example, aperture 28 can be 
dimensioned and shaped to accept the button of a push-button type switch 
or may be simply a circular hole dimensioned to accomodate the shank or 
shaft of either a rotary or linear dimmer, or of a rotary or turn-switch. 
It will be seen, particularly in FIG. 2, that the thickness of insert 26 is 
equal to or greater than the thickness of plate 20 at opening 22, i.e. as 
shown at "d" in FIG. 2. This structural requirement insures that when the 
edge portion of the insert is an upstanding ridge as will be hereinafter 
described, the ridge will always project beyond the adjacent surface of 
the plate. 
Means are provided for securing insert 26 within aperture 22. To this end, 
insert 26 is preferably dimensioned so as to fit snugly within aperture 
22, and thus may be press-fitted. Alternatively, insert 26 may be made of 
a slightly resilient material such as a high molecular weight polymer, in 
which case, as shown particularly in FIG. 3, the insert is provided with 
narrow peripheral groove 27 so that it may be deformably snapped into 
aperture 22. In a preferred form, particularly as shown in FIG. 2, insert 
26 is provided with a circumferential ridge or lip 29 adapted to butt 
against the underside of outer or facing surface 30 of plate 20 and may be 
thereby attached to the underside of plate 20 by adhesive or the like, by 
press-fit or by any other well-known means. Where insert 26 is provided 
with lip 29, the latter may also be appropriately apertured, as shown at 
32 in FIG. 4, to accept fasteners such as screws which are intended to 
connect the insert to the frame of an electrical control means or the like 
mounted within a wall box, or alternatively to the plate per se. 
Importantly, the present invention includes means 36 disposed on the edge 
portions of insert 26 for providing a luminance mask or visual 
discontinuity between front surface 30 of plate 20 and the front surface 
34 of insert 26, surface 34 being that portion which is bounded by the 
aforementioned edge portions It is known that the psychological 
effectiveness of a light stimulus is altered by introduction of a similar 
stimulus at the same time. Such visual interaction is illustrated by fact 
that introduction of a third or inducing object between two other objects 
being matched for brightness will alter the match, keeping in mind that 
brightness is the psychological or perceived effect of viewing a given 
stimulus provided by the luminance of an object. The effect of such visual 
interaction is known as meta-contrast or masking The necessary visual 
discontinuity to provide masking can be achieved, for example, by 
disposing between adjacent outer surfaces of the insert and plate and on 
the edge portions of insert 26, frame or ridge 36 designed in one 
embodiment to project outwardly beyond the plane of surface 34 when insert 
26 is properly positioned within aperture 22. The cross-sectional shape of 
ridge 36 may be varied and for example can be rectangular, rounded, 
rhomboid, triangular or the like. Alternatively, the visual discontinuity 
need not be a ridge but may be an edge inlay or painted stripe of 
contrasting luminance, or a groove which in effect is a reversal of the 
reentrant cross-section of ridge 36. The essential attribute of ridge 36 
is that it psychologically masks variations in shade or luminance between 
the surface of the plate and the surface of the insert. For example, if 
both the plate and the insert are slightly different shades of white, the 
presence of ridge 36 as an upstanding frame will tend to throw a shadow 
(except in the rare instance where the light impinging on the wall plate 
is perpendicular to the plane of the front surface of the latter), and 
either the shadow or the surface of the discontinuity will provide the 
desired masking effect. It will be appreciated that this shadow will serve 
also to hide or reduce the effect of an angular mismatch between the 
planes of the adjacent respective surfaces of the plate and the insert. 
While a groove or stripe will provide a like, if not as strong, a 
luminance masking effect, they will not yield the desired shadowing, so 
the ridge embodiment is preferred. 
Another embodiment of the present invention is shown in FIGS. 5 and 6 
wherein decorator wall plate 20, as previously shown and described in 
connection with FIG. 1, accepts insert 26 connected to or formed as part 
of electrical control means 40. Insert 26 in this embodiment includes 
multiple apertures 28a and 28b for accepting several control elements such 
as switch 42 and removable control knob 44 for dimmers and the like, 
switch 42 and knob 44 being typically coupled to electrical control means 
40. Means 36 thus serves as a frame to surround the manually operable 
levers or knobs of electrical control elements extending through apertures 
28 and aid in locating the several control levers as well as to soften the 
angular appearance of the latter. For example, typically knob 44 is a 
manually linearly slidable or rotatable control member coupled to a dimmer 
circuit, while element 42 is typically a tumbler-switch lever, a 
turn-switch knob or the button of a push-button switch cooperating with 
the dimmer circuit to control a lighting circuit. Electrical control means 
40 is shown mounted on conventional wall 46 in conventional wall box 48 as 
by screws 50, snaps 52 being provided to secure insert 26 to control means 
40. As in the earlier described embodiment, means 36 also provides a 
luminance mask or visual discontinuity between front surface 34 and wall 
plate 20. 
As shown in FIG. 7, insert 26 of FIG. 5 features snaps 52 for coupling 
insert 26 to control means 40. Due to the resilient nature of the polymer 
from which insert 52 is preferably formed, snaps 52 permit ready removal 
of insert from control means 40, for purposes of changing the color or 
design of the insert according as the user prefers. Multiple appertures 
28a and 28b are so sized that once control knob 44 has been removed, 
insert 26 may simply be unsnapped from control means 40. 
Yet another embodiment of the present invention is shown in FIGS. 8 and 9 
wherein decorator wall plate 20 has openings 22 in which is located insert 
26, the latter being dimensioned to fit snugly in opening 22 as previously 
described herein. A visual discontinuity is provided between the outside 
surface of plate 20 and surface 34 of insert 26 by groove 60, surface 34 
being generally disposed to lie in a plane somewhat above the plane of the 
surface of plate 20. Groove 60 is bounded about its exterior edges by lip 
62 formed about the periphery of insert 26 to mask from direct view any 
internal mechanisms of controls or switches. Multiple apertures 28c, 28d 
and 28e are provided in insert 26 to provide space through which can be 
extended or observed visual indicators or operators of control functions, 
such as on/off indicator light 64, LED bargraph 66 or control switch 68. 
Since these and other changes may be made in the above apparatus without 
departing from the scope of the invention herein involved, it is intended 
that all matter contained in the above description or shown in the 
accompanying drawings shall be interpreted in an illustrative and not in a 
limiting sense.