Patent Application
20120068894
1. Technical Field
The subject matter described herein relates to wall mounted electrical control devices that can be remotely controlled and monitored via radio frequency transmissions. The subject matter described herein also relates to remote control devices for controlling and monitoring the wall mounted electrical control devices. More particularly, the subject matter described herein relates to electrical devices that can include one or more interchangeable key capsules, one or more associated interchangeable bezel frames which include a radio frequency antenna element, and one or more interchangeable radio frequency circuitry components.
2. Background Art
The field of home automation is rapidly developing. The ability to control electrical fixtures, appliances, and electronics remotely or through a central location is becoming more and more common place. Remote electronic control devices, such as lighting dimmers, include control circuitry and processors which can be powered by internal power supplies that derive power from high voltage house wiring that is typically 120 VAC (volts, alternating current) in the United States.
Wall mounted switching devices such as light switches and dimmers are typically placed inside a junction box or mounting fixture. In commercial construction, metal wallboxes are often used. A metal electrical wallbox along with a metal faceplate can act as a Faraday cage that significantly attenuates the transmission of radio frequency electromagnetic radiation from the antenna. As such, antenna location is an important factor.
Traditional radio Frequency (RF)-Controlled lighting dimmers have typically operated using RF frequencies, such as 418 megahertz (MHz), that have a relatively long ¼ wavelength (i.e. 6¾ inches) with respect to the physical dimensions of a residential single-gang wallbox that conforms to National Electrical Manufacturers Association (NEMA) specifications (i.e., 2¼ inches (W)×3¾ inches (L)×3¼ inches (D)). Those skilled in the art will recognize that the physical dimensions of an antenna, particularly the ‘length’ dimension, are primary determined by the ¼ wavelength (λ) of the operating frequency of the antenna. Various methods have been employed in the prior art to accommodate undesirable long antennas used to satisfy the ¼ wavelength (λ) standard at operational frequencies such as 418 MHz.
As an example, some traditional devices use a printed circuit board (PCB) antenna that includes capacitors to help balance the inherent inductive load. Prior art
Prior art
An illustrative electrical device configured to install within a wall mounted electrical box includes a bezel frame that fits within a faceplate. The bezel frame includes an antenna element. The device further includes a radio frequency circuitry component in electrical communication with the antenna element and configured to receive a control signal from the antenna element.
An illustrative device kit includes a first antenna bezel frame and a first antenna element. The first antenna element is mounted to the first antenna bezel frame such that the first antenna element is located a distance forward of a plane that contains a front surface of a faceplate when the first antenna bezel frame is installed in a field configurable electrical device. At least a portion of the first antenna bezel frame that includes the first antenna element protrudes through an opening in the faceplate.
Other principal features and advantages will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims.
The accompanying figures further illustrate the present invention. The components in the drawings are not necessarily drawn to scale, emphasis instead being placed upon clearly illustrating the principles of the present subject matter. In the drawings, like reference numerals designate corresponding parts throughout the several views.
Prior art
Prior art
Prior art
Prior art
The following is a list of the major elements in the drawings in numerical order.
Reference will now be made to the illustrative embodiments depicted in the drawings, and specific language will be used herein to describe the same. It will nevertheless be understood that no limitation of the scope of the subject matter described herein is thereby intended. Alterations and further modifications of the embodiments illustrated and described herein, and additional applications of the embodiments illustrated and described herein, which would occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the subject matter described herein. Unless the context clearly requires otherwise, throughout the description and the claims, the words ‘comprise’, ‘comprising’, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.
In the last several years, wireless infrastructure has developed at a rapid pace. Residential home wireless networks are now common place. Standards like “Bluetooth”, “Wi-Fi”, “Zigbee”, and “Zwave” have been developed and each of these standards allow multiple wireless devices, from various vendors, to coexist. Advantageously, these new wireless standards typically operate in relatively high frequency bands, such as the ISM band centered about 2.440 GHz, that have correspondingly short wavelengths (e.g., ¼ wavelength=1.2 inches). As such, the inventors have perceived that it is possible to design traditional antenna configurations (i.e. monopole, dipole, etc.) within the physical dimensions of a residential single-gang wallbox for a device that operates in the GHz range. At the relatively short ¼ wavelengths (λ) associated with frequencies such as 2.440 GHz, special antenna configurations such as the those used in the prior art can be avoided.
As described above, the prior art antenna systems for wall-mounted dimmers are located behind a front surface of the faceplate and have a limited ability to transmit/receive due to interference, poor reception, etc. In addition, because of the low, static frequencies used in the prior art, existing devices do not allow for field-modifying of an RF controlled device to operate at a different operating frequency.
Described herein is a field configurable electrical device such as a light dimmer where the antenna element and the radio frequency (RF) circuitry component (or transceiver) can be changed to an alternate operating frequency (i.e. 2.440 GHz, 3.670 GHz, 5.220 GHz, etc.) in the situation where interference is experienced at a particular frequency. The RF circuitry component can be in the form of a miniaturized packaged configuration, such as a monolithic surface mounted integrated circuit, so that design can be standardized among various vendors and more complex circuitry can be used. The antenna element is mounted to a bezel frame to allow for rapid replacement of the antenna element (and bezel frame) if a change in operating frequency is implemented. In an illustrative embodiment, the bezel frame and the antenna element mounted thereto extend outward from a front surface of a faceplate (through an opening in the faceplate) so that the effect of surrounding metal, such as metal faceplates, and other components on antenna performance is minimized. The field configurable electrical device is also configurable in an aesthetically pleasing manner in order to provide for a uniform look with other appliances. In alternative embodiments, the electrical devices described herein may not be field configurable.
Refer now to
The antenna bezel frame 74 and the associated color-matched elements are located in front of a housing 71 that contains various electronic components, including control circuitry that is used to control the load based on control commands received through the rocker switch actuator 618 or from a remote control unit. The control circuitry can include and/or be in communication with a microprocessor as known to those of skill in the art. In one embodiment, the control circuitry may include a gated electronic switching device, such as a triac, in order to control voltage going to the load. Alternatively, other types of control circuits known to those of skill in the art may also be used. The housing 71 also houses an RF circuitry component 722 (illustrated in
Light pipes 735 transmit light from status indicators, such as light-emitting diodes (LED), located within housing 71, for external visibility. The LEDs can indicate the dimmer setting of the load, the on/off status of the load, the speed of the load, etc. In one embodiment, a sensor assembly including a sensor may be mounted within the antenna bezel frame 74. The sensor can be configured to sense one or more environmental parameters such as infra-red, ultrasonic, humidity, temperature, ambient light, etc. In such an embodiment, the LEDs and/or a liquid crystal display (or other type of display) can be used to display the sensor reading(s).
The inventors have discovered that widespread development of digital communication in the gigahertz (GHz) frequency range provides many potential benefits, such as small antenna size, immunity from electrical and triac switching noise, and higher emitted power being allowed by regulatory authorities such as the Federal Communications Commission (FCC). The inventors have also discovered that these benefits can be used in RF-controlled residential devices such as the field configurable electrical device. In one embodiment, the antenna element 742 is a ⅝ wavelength (λ) ‘F’ type antenna element developed to operate within an ISM frequency band centered around 2.440 GHz. In other embodiments, the antenna element 742 and the RF circuitry component 722 can be designed to operate within other frequency bands, such those centered about 3.670 GHz, 5.220 GHz, etc. Should other gigahertz frequency bands become allocated for the purpose of home automation, the antenna element 742 can be adapted to be compatible with those bands. As discussed in more detail with reference to
In an illustrative embodiment, the antenna element 742 is mounted to or within the antenna bezel frame 74 and is connected to the RF circuitry component 722 (shown in
In contrast to some prior art implementations in which the antenna is located behind one or more key capsules, the antenna element 742 of the field configurable electrical device is located to the side of the key capsules (or buttons), which allows for the use of metallic decorative elements on the key capsules where the use of such decorative elements would not be practical using the antennas taught in the prior art. In one embodiment, the key capsules used with the field configurable electrical device may even be made from a metal, such as aluminum. In prior art systems in which an antenna is mounted behind the key capsule, a metal key capsule would lead to interference and poor reception, and would be impractical. Alternatively, plastic may also be used for the key capsule(s).
Refer now to
Refer now to
The measured results illustrated in
In an illustrative embodiment in which the field configurable electrical device is a local unit, the antenna element 742 can be used to communicate with a remote device such as a remote control (i.e., master) field configurable electrical device or a separate local field configurable electrical device. For example, a remote control field configurable electrical device can be used to control the lighting within a house, room, or building. The remote control field configurable electrical device can communicate with the local field configurable electrical device via the antenna element 742. The remote control field configurable electrical device can, in response to a user command, transmit a control signal to the antenna element 742 such that a user can remotely control the load (i.e., turn the load on/off, adjust the speed of the load, adjust a dimmer setting of the load, etc.). The control signal is received by the antenna element and provided to the radio frequency circuitry component 722 through the spring-loaded connectors 731 and 732. Control information can be obtained from the control signal using the RF circuitry component 722 and/or other components such as a microprocessor, etc. by any method known to those of skill in the art. Control circuitry can be used to control the load based on the control information. Status information can also be transmitted by the antenna element 742 of the local field configurable electrical device to an antenna element of the remote control field configurable electrical device to provide the remote control field configurable electrical device with a status of the local field configurable electrical device. For example, the local field configurable electrical device may transmit information regarding a most recent command received at the local field configurable electrical device (regardless of whether the command originated at the local unit or the remote control unit). The remote control unit can receive the status information and update a display (such as one or more LEDs, a liquid crystal display, etc.) that presents the status of the local unit.
In an illustrative embodiment, the field configurable electrical devices described herein can be configured to be nodes of a mesh network. A wireless network based on the IEEE 802.11b/g standard typically has each node in the network communicate with a central source, which is typically part of a wired network. In contrast, each node in a mesh network can communicate with other nodes in the network. In one embodiment, every node in the mesh network can communicate with every other node. In another embodiment, nodes can communicate with other intermediary nodes in the mesh network that are not within radio frequency range. As such, devices which are remotely located from one another (i.e., out of range) may be able to communicate to one another through other devices in the mesh network.
The housing 71 further comprises the housing cover 73, an electrical interface assembly 72, a support plate 42, and a back housing portion 41. The support plate 42, which can be formed from a material having a high thermal and electrical conductivity, such as aluminum, can be used to dissipate heat from the triac or other control circuitry components. The support plate 42 can also act to provide RF shielding between the antenna element and other electronics components mounted within the housing 72.
The electrical interface assembly 72 includes the RF circuitry component 722, status indicators 725 (such as LEDs), pushbutton switches 728, and a connector 721 to connect with the remainder of the electrical components that are mounted in the back housing portion 41. Advantageously, adding the connector 721 to the electrical assembly 72 allows for easy change-out or replacement of the RF circuitry component 722. The housing cover 73 includes light pipes 735 to transmit light from the status indicators on the electrical interface assembly 72 to a user of the device through the antenna bezel frame 74. The housing 71 may further house a power supply circuit (and/or regulator) as known to those of skill in the art. The power supply circuit can be wired in parallel with a controlled load and that is directly connected to electrical neutral. Alternatively, the power supply circuit may be wired in series with the controlled load and may be connected to electrical neutral only through the controlled load. Alternatively, any other wiring configuration known to those of skill in the art may be used.
The housing 71 may further house a computer-readable medium, such as a tangible memory, that is configured to store computer-readable instructions. The computer-readable instructions can be executed by a microprocessor and/or other components of the field configurable electrical device. Upon execution, the computer-readable instructions can cause the field configurable electrical device to perform any of the operations described herein, such as controlling the load, extracting control information from a control signal, generating status information to be transmitted, etc.
In one embodiment, the field configurable electrical device can be provided as a kit that includes at least two bezel frames, where each of the bezel frames has a mounted antenna element that operates at a different operating frequency. The kit can also include at least two radio frequency circuitry components that correspond to the at least two operating frequencies of the antenna elements. As such, in the event of noise or signal interference, a user can replace the first bezel frame (and antenna element) and the first RF circuitry component operating at a first frequency with the second bezel frame (and antenna element) and the second RF circuitry component operating at a second frequency. Additional sets of bezel frames and RF circuitry components may also be included in the kit. As an example, RF interference may result from the use of the field configurable electrical device with a first bezel frame (including a first antenna element) and a first RF circuitry component that operate at a first frequency of 2.440 GHz. To eliminate the RF interference, the first bezel frame (and the first antenna element) and the first RF circuitry component can be replaced with a second bezel frame (including a second antenna element) and a second RF circuitry component which operate at a second frequency of 3.670 GHz. In one embodiment, the kit can also include a plurality of key capsule configurations.
Although dimmers have specifically been mentioned, additional embodiments can include other devices mounted in an electrical wallbox, such as keypads.
The embodiments described herein solve the aforementioned problems in the prior art and have wide ranging industrial applicability. The field configurable electrical devices are modular to help prevent and avoid RF interference. The field configurable electrical device also utilize an antenna element configuration that results in improved reception and transmission. The antenna element configuration, along with the frequency ranges used, also contribute to devices that are aesthetically pleasing.
The following is a list of the acronyms/abbreviations/symbols used in the specification in alphabetical order.
The foregoing description of illustrative embodiments has been presented for purposes of illustration and of description. It is not intended to be exhaustive or limiting with respect to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosed embodiments. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13037709 | Mar 2011 | US |
| Child | 13305914 | US | |
| Parent | 12757407 | Apr 2010 | US |
| Child | 13037709 | US | |
| Parent | 12606886 | Oct 2009 | US |
| Child | 12757407 | US |
