This invention relates to a novel covering assembly for a wall box mounted switch, receptacle or other device of the type which employs an integral yoke plate having standard screw holes at the yoke plate positioned the same as those at a wall box.
Wall box mounted devices and switches are well known. Conventional cover plate assemblies world widely used are mounted on switch devices or frames or yoke plates carried with switch mechanisms. Switch manufacturers in some countries produce cover plate assemblies based on the mounting structures of their own switch devices. The traditional concept guides inventors to invent various decorative switch cover plate assemblies based on the types of switch devices provided and the mounting rules established by the switch manufacturers.
Besides, conventional switch cover plate assemblies are either made of plastic to hide mounting screws or made of metal to expose mounting screws. Conventional switch cover plates with the face plate free of mounting screws are not suitable for metal structures with snap fit connections because the metal snaps are subject to breaking at installation. As a matter of fact, metal plates have better decorative appearances than those of plastic ones.
Although wall boxes for switch devices are in universal standard, conventional cover plate assemblies for switch devices are not. A universal cover plate assembly for a universal switch device has many obvious advantages. Manufacturers shall have more broad sales markets world widely. House owners shall have more choices in selecting decorative covering assemblies from the world wide market. Manufacturers shall also find that a universal cover plate can greatly reduce number of production molds for decorative covering plates. The advantages provide tremendous benefits to both house owners and manufacturers.
As a matter of fact, screw holes for wall box mounted switch devices are positioned in universal standard. A switch mechanism having a yoke plate with screw holes positioned in universal standard can be provided as a universal switch device. A cover plate assembly with its mounting structure independent from a switch device and having its screw holes aligned with those at a wall box can also be provided as a universal cover plate assembly.
In combination, a novel cover plate assembly made of metal with face plate free of screw holes for a switch mechanism having a yoke plate with screw holes positioned in universal standard is not solved by prior art devices.
Accordingly, a principal object of the present invention is to provide a switch mechanism having a simple yoke plate and a novel cover plate assembly comprising of a base plate and a face plate. The face plate is free of mounting screw openings.
An important object of the invention is to fabricate a cover plate assembly from metal so that better structure quality and decorative appearance can be provided.
Another object of the invention is to provide a universal cover plate assembly having a snap fit connection between the face plate and the base plate.
Another object of the invention is to provide a universal cover plate assembly which is demountable and replaceable.
Another object of the invention is to provide a universal cover plate assembly having the base plate mounted to a wall box instead of a switch device.
Another object of this invention is to provide the base plate as an independent platform to receive switch devices and to maintain alignment of the switch device against the wall.
Another object of the invention to provide a switch mechanism having a yoke plate with round-shaped screw holes spaced the same as those at the base plate and those at a wall box. Ears for alignment and threaded screw holes for conventional cover plates at yoke plates of switch devices of prior art are useless for the structure of the present invention.
Another object of the invention is to fabricate the face plates from steel plate by employing punch presses. The orifices at face plates are punched at the last stage with separated molds for the shapes of the orifices.
The present invention systematizes a novel cover plate assembly and a switch mechanism having a yoke plate as a universal wall box mounting structure for any devices of any types. The cover plate assembly can be made of metal to provide noble appearances for wall decorations. The novel cover plate assembly comprises of a face plate and a base plate with the face plate free of mounting screws. The face plate is snapped into the base plate by a snap fit connection. The switch mechanism is mounted to a wall box through a yoke plate together with the base plate. The base plate has an opening sufficiently large to receive switch devices.
70 wall box
71 and 72 screw hole
60 base plate
61 and 62 screw hole
63, 64, 65 and 66 snap receiving opening
68 edge
69 central opening
40 switch device
45 switch mechanism
46 control member
43 yoke plate
41 and 42 screw hole
31 and 32 screw
20 face plate
21, 22, 23 and 24 snap
26 orifice
81 and 82 prying hole
91, 92, 93 and 94 screw
101, 102, 103 and 104 screw hole
201, 202, 203 and 204 screw hole
I. Preferred Embodiment Switch Cover Plate Assembly
Referring first to
Base plate 60 has cover plate openings or screw holes 61 and 62 which match the center-to-center spacing of threaded screw holes 71 and 72. Snap receiving openings 63, 64, 65 and 66 are symmetrically located next to the inner periphery of edge 68, which are aligned with snaps 21, 22, 23, 24 at face plate 20 for a snap fit connection. Central opening 69 is adapted for receiving switch device 40. Central opening 69 is also adapted for passage of switch device 40 with connected wires moved from the rear side of base plate 60 to the front side for cover plate assembly replacement. The inner periphery of edge 68 at base plate 60 is slightly large than the outer periphery of face plate 20 so that base plate 60 can receive face plate 20.
Switch device 40 is of the type for fan speed control. The present invention applies to any other types of switch mechanisms or devices for lighting and the like. Switch device 40 consists of a switch mechanism 45, a yoke plate 43 and a control member 46. Switch mechanism 45 is lifted and supported by yoke plate 43 to be connected to wall box 70 through base plate 60. Yoke plate 43 preferably is a generally flat thin metal plate. However, it can also be molded of flame retardant materials such as plastic as long as it is strong enough to carry switch mechanism 40. Screw holes 41 and 42 at yoke plate 43 of this invention are in round shape having a diameter slightly larger than the one of the screw. Conventional switch devices provide laterally elongated openings for positioning alignment at installation. Such positioning alignment, however, is not necessary for installation of switch device 40 with the cover plate assembly of the present invention. Considering the wide use of conventional cover plates, it is optional to keep conventional threaded screw mounting holes at yoke plate 43 of the present invention for mounting cover plates of prior art.
Screws holes 41 and 42 at yoke plate 43 are on a spacing equal to that of screw holes 61 and 62 at base plate 60 and screws holes 71 and 72 at wall box 70. Fasteners or screws 31 and 32 pass through screw holes 41 and 42 and screw holes 61 and 62, respectively, and are threaded into screw holes 71 and 72 respectively to mount both base plate 60 and switch device 40 to wall box 70 at the same time. Base plate 60 mounted to wall box 70 maintains alignment of switch device 40 and receives face plate 20 stably. As it is seen, the cover plate assembly with base plate 60 is not mounted into switch device 40 but into wall box 70. The cover plate assembly is therefore an independent structure from switch devices. Conventional cover plate assemblies are used to be mounted into switch devices or yoke plates or special frames carried with switch mechanisms.
Face plate 20 is snapped into base plate 60 for interlocking engagement. Orifice 26 at face plate 20 is adapted to permit control member 46 of switch device 40 to extend through face plate 20. A snap connection structure is illustrated in
Referring now to
III. Alternative Embodiment Switch Cover Plate Assembly
Alternatively, the components of the cover plate assembly of the present invention can also be molded of any materials such as plastic.
The second alternative embodiment of the present invention is to arrange snaps at a molded face plate and snap receiving openings at a molded base plate at locations other than those shown in the preferred embodiment. Referring now to
As it is seen, the cover plate assembly of the present invention applies to any switch mechanisms or devices having simple yoke plates with screws holes at the yoke plate positioned in universal standard.
Alternatively, the structure of the cover plate assembly of the present invention can be used for other purposes such as for door lock covers and wall-mounted metal pictures. Noble surface appearance of the metal picture is super for wall decoration.
While certain preferred and alternative embodiments of the invention have been set forth for purposes of disclosure, modifications to the disclosed embodiments as well as other embodiments thereof may occurred to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments of the invention and modifications thereof which do not depart from the spirit and scope of the invention.