Patent Publication Number: US-7708418-B2

Title: Support frame for electrical apparatuses

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present application is a national filing in the U.S. Patent &amp; Trademark Office of PCT/IT2006/000217 filed Apr. 3, 2006, and claims priority of Italy Patent Application No. RM2005A000164 filed Apr. 7, 2005, both of which applications are incorporated herein in their entireties by this reference. 
   FIELD OF THE INVENTION 
   The present invention refers to the technical field of electric installations of dwellings and offices, and more specifically, concerns a support frame for wall-mounting an electrical apparatus. 
   BACKGROUND OF THE INVENTION 
   For the purposes of the present description, by electrical apparatus we mean, in general, any means or electrical device generally forming part of electric installations in civil buildings and the like and usually intended to be mounted, for example built in, onto walls of such buildings. 
   This definition therefore includes, not limitingly, switches, electrical power sockets, sockets for data networks, TV sockets, telephone sockets, buttons, commutators, deviators, electrical adjustment devices in general, connectors, thermostats, timers, fuse-boxes, alarms/buzzers, emergency lights (for example removable), indicator lights (for example guidance lights), displays (for example LCD) and the like. 
   As known, many of the aforementioned electrical apparatuses are usually installed on a wall using composite mounting structures, or groups of parts, generally including:
         a box intended to be built into the wall;   a apparatus-carrying mounting frame (or support frame) that can be fixed to the box and comprising a frame body extending around an opening defining a mounting seat suitable for receiving and holding one or more electrical apparatuses; and   a cover plate that can be fixed to the frame and provided with an opening to allow a user to gain access, visually or manually, to the electrical apparatuses installed on the support frame.       

   There is a great requirement to make a mounting group that allows a user to easily identify it even in poorly lit locations. 
   SUMMARY OF THE INVENTION 
   Such a requirement is satisfied through a support frame as defined in the attached first claim in its most general form and in the dependent claims in some particular embodiments. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention shall be better understood from the following detailed description of two embodiments thereof given as an example and, therefore, in no way limiting, referring to the attached drawings, in which: 
       FIG. 1  is an axonometric view of a particularly preferred embodiment of a support frame in accordance with the present invention; 
       FIG. 2  is a simplified circuit diagram of the support frame of  FIG. 1 ; and 
       FIG. 3  shows a front view of a cover plate and of a group of electrical apparatuses applied to the support frame of  FIG. 1 . 
   

   In the figures, identical or similar elements shall be indicated through the same reference numerals. 
   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   In  FIG. 1  a particularly preferred embodiment of a support frame in accordance with the present invention is shown. 
   The support frame, globally indicated with  1 , includes a frame body  2 , preferably made from insulating material and having approximately the shape of a substantially plate-shaped framework, for example, in a non-limiting way, with quadrangular plan. 
   The support frame  1  includes means for fastening to the wall, for example it includes a pair of holes  3  passing through the body  2  of the frame  1 , preferably slotted, suitable for receiving respective screws to fix the support frame  1  to a box built in to the wall. 
   The support frame  1  also includes coupling means for coupling the frame  1  with a cover plate, not represented in  FIG. 1 . In the example represented in  FIG. 1 , such coupling means in a non-limiting way are in the form of four coupling channels  4  suitable for receiving respective fastening tabs foreseen in the cover plate. 
   As is known to men skilled in the art, the role of such a cover plate is both that of ensuring a minimum protection for the electrical apparatuses, for example from dust, and that of preventing dangerous access (for example through pointed objects) to the electrically conducting parts of the electrical apparatuses. Another fundamental task assigned to the cover plates is also that of masking unpleasant sights produced for example by the presence of a recess in the wall, and by the presence of the box and of the mounting frame that, rather than having an aesthetic value, have a functional value that is difficult to combine with aesthetic requirements or standards. 
   The body  2  of the frame  1  extends around a main opening  5 , defining a mounting seat suitable for receiving or holding one or more electrical apparatuses, not represented in  FIG. 1 . A plurality of hooking elements  6  project from the body  2  of the support frame  1  towards said opening  5 , preferably along two parallel edges of the body  2  of the frame  1  that define such an opening  5 . Such hooking elements  6  are such as to cooperate with corresponding hooking elements foreseen on two opposite sides of the electrical apparatuses to be hooked to the support frame  1 . Preferably, the hooking elements  6  allow hooking of the interlocking type of the electrical apparatuses to the support frame  1  to be carried out. 
   Advantageously, the support frame  1  includes at least one optical source  7 . 1 ,  7 . 2  suitable for emitting an optical signal having at least one portion of spectrum in the visual range. 
   Preferably, such an optical source  7 . 1 ,  7 . 2  is an opto-electronic device, preferably of the LED type, for example with emission in the blue range. In a particularly preferred embodiment, such an optical source includes a first LED device  7 . 1  and a second LED device  7 . 2 , arranged on respective sides of the body of the frame  2 , opposite to the opening  6 . Preferably, but not in a limiting way, the LEDs  7 . 1  and  7 . 2  are miniaturised devices made with surface mounting technology (SMT). From this point on, in the present description reference shall be made to the particular example in which the support frame includes two optical sources, without for this reason introducing any limitation upon the number of sources used. 
   Advantageously, the support frame  1  also includes an electrical circuit suitable for providing the optical sources  7 . 1 ,  7 . 2  with an electrical power supply signal. Preferably, at least one part of the electrical circuit is made on one or more printed circuits that also acts as a support for the optical sources. In the example of  FIG. 1 , since the support frame  1  includes two optical sources  7 . 1 ,  7 . 2 , the electrical circuit includes two printed circuit boards,  8 . 1  and  8 . 2 , on each of which a respective LED  7 . 1 ,  7 . 2  is welded. It should be observed that in  FIG. 1  the LEDs are fixed onto the printed circuit boards on their side facing towards a possible cover plate to be fixed to the frame. Alternatively, the optical sources could be mounted onto the printed circuit boards on their side intended to face the mounting wall for the support frame  1 . 
   The circuit diagram  20  of the support frame of  FIG. 1  is shown in  FIG. 2 . The electrical circuit of the support frame  1 , globally indicated with  20 , includes two input terminals  9 . 1 ,  9 . 2 , in the example arranged on the first printed circuit board  8 . 1 . These terminals  9 . 1 ,  9 . 2  are such as to receive in input an alternating voltage from the mains power supply, preferably the same alternating voltage that can be fed in input to the electrical apparatuses intended to be fixed to the support frame  1 . For example, respective small cables (not shown in the figures) can be welded to the terminals  9 . 1  and  9 . 2  to connect such terminals  9 . 1 ,  9 . 2  to the mains alternating voltage. 
   The electrical circuit  20  also includes a transformation circuit section  10  connected to such input terminals  9 . 1 ,  9 . 2  to receive such alternating voltage in input and transform it into a continuous feed voltage suitable for feeding the LEDs  7 . 1 ,  7 . 2 . In particular, the continuous feed voltage is made available to two output terminals  11 . 1 ,  11 . 2  of the transformation circuit section  10 . The details of a circuit section  10  suitable for transforming an alternating voltage into a continuous voltage form part of the general background knowledge of a man skilled in the art and for this reason they shall not be described any further. 
   One of the output terminals of the transformation circuit section  10 , i.e. the terminal  11 . 1 , is connected to a terminal of the LED  7 . 1 . The other terminal of the LED  7 . 1  is connected to a first output terminal  12 . 1  of the first printed circuit board  8 . 1 . 
   The other  12 . 2  of the two output terminals of the transformation circuit section  10  is electrically connected to a second output terminal  12 . 2  of the first printed circuit board  8 . 1 . 
   Electrical connection means  13 . 1 ,  13 . 2 ,  14  are provided in the circuit  20  to connect the first  8 . 1  and the second  8 . 2  printed circuit board, and therefore the first  7 . 1  and the second  7 . 2  optical source together. Such connection means include, for example, a pair of conducting cables  13 . 1 ,  13 . 2  equipped with insulating sheath. As an alternative to the two conducting cables  13 . 1 ,  13 . 2 , to make the connection between the two boards  8 . 1 ,  8 . 2  two conductive tracks printed onto a band of insulating and flexible material could be used. 
   The conducting cables  13 . 1 ,  13 . 2  are respectively such as to connect the first/second output terminal  12 . 1 ,  12 . 2  of the first printed circuit board  8 . 1  to a first/second input terminal  15 . 1 ,  15 . 2  of the second printed circuit board  8 . 2 . 
   The electrical connection means  13 . 1 ,  13 . 2 ,  14  of the circuit  20  also include switch means  14  for opening/closing the electrical connection between the two printed circuit boards  8 . 1 ,  8 . 2 . In the example, such switch means include a switch  14  suitable for connecting/disconnecting two intermediate terminals  14 . 1 ,  14 . 2  of one  13 . 1  of the two connection cables  13 . 1 ,  13 . 2 . 
   The second LED device  7 . 2  is connected in series between the two input terminals  15 . 1 ,  15 . 2  of the second printed circuit  8 . 2 . 
   It should be observed that in practice in the circuit  20  represented in  FIG. 2 , the two LEDs  7 . 1 ,  7 . 2  and the switch  14  are connected together in series. It should also be observed that such a switch  14  is such as to interrupt/restore a power supply current of the LEDs  7 . 1  and  7 . 2 , supplied by the transformation circuit section  10 . 
   Going back to the support frame  1  represented in  FIG. 1 , advantageously, the body of the frame  2 , includes one or more pockets or inner chambers, made in the profile of said body  2  to receive the electrical circuit and the optical sources inside of it. 
   In the example of  FIG. 1 , the frame body includes two inner chambers  16 . 1  and  16 . 2  each of which receives a respective LED  7 . 1  and  7 . 2 , and a respective printed circuit board  9 . 1 ,  9 . 2 . Each inner chamber  16 . 1 ,  16 . 2  is preferably formed from a pocket made in the profile of the frame body  1  and from a cover element  17 . 1 ,  17 . 2 , for example substantially plate-shaped, suitable for closing an open side of such a pocket to form a substantially closed chamber  16 . 1 ,  16 . 2 . 
   In a particularly preferred embodiment, the body  2  of the support frame  1  and the cover elements  17 . 1 ,  17 . 2  of the chambers  16 . 1 ,  16 . 2  housing the optical sources  7 . 1 ,  7 . 2  are made from a material substantially transparent to the wavelength of the optical signals emitted by such sources. Preferably, such a material is a hard and transparent plastic. Nevertheless, it should be observed that it is not essential that the entire body  2  of the frame  1 , including the cover elements  17 . 1 ,  17 . 2 , be made from a transparent material. Indeed, it is sufficient for just a portion thereof be transparent in such a way as to be able to make at least one portion of the optical signals emitted by the sources pass to outside the frame. Of course, it is possible to make a support frame having both transparent parts and opaque parts but it is more expensive, therefore less preferred, than making a frame completely from a transparent material. 
   Preferably, the optical signals generated by the LED sources escape by propagation outside of the frame body on two peripheral sides  2 . 1 ,  2 . 2  of the frame body  2  opposite to the opening  5 . 
   Preferably, a further inner chamber  16 . 3  is foreseen in the body  2  of the frame to in part receive the switch  14 . This further inner chamber  16 . 3  is also formed from a pocket provided with an open side and from a cover element  17 . 3  suitable for closing such an open side to form a substantially closed chamber  16 . 3 . 
   In the particular example represented in  FIG. 1 , the switch  14  includes an actuation lever  21  that can rotate about a pin  22 . A first intermediate end of the conducting cable  13 . 1 , for example welded to a bent sheet  23 , makes a fixed contact element of the switch  14 . A second end  14 . 3  of the conducting cable  13 . 1 , for example welded to a plug, is fixed to a support arm  24  connected to the actuation lever  21  and makes a mobile contact element of the switch  14 . The switch  14  can however be different to the particular example of switch described. 
   In a particularly preferred embodiment, the body  2  of the support frame  1  includes a channel  25 , made in the profile of the body  2  of the frame  1 , suitable for receiving inside it the electrical connection means  13 . 1 ,  13 . 2  between the first  7 . 1  and the second  7 . 2  optical source. Preferably, the channel  25  extends along a side of the opening  5  to place the first inner chamber  16 . 1  in communication with the second inner chamber  16 . 2 . More preferably, as represented in  FIG. 1 , the channel  25  crosses the third inner chamber  16 . 3  housing part of the switch  14 . 
     FIG. 3  shows a cover plate  30  fixed to the support frame  1 . Three electrical apparatuses, for example three button-actuated switches  31 , are installed in the mounting seat of the support frame  1 . The mounting frame  1  has its front portion completely covered by the cover plate, and for this reason it cannot be seen in  FIG. 3 , with the exception of the actuation lever  21  that projects from a lower edge  30 . 1  of the cover plate  30 . 
   As can be seen in  FIG. 3 , the cover plate  30  acts as an opaque screen for the optical signals emitted by the optical sources  7 . 1 ,  7 . 2 , in other words, the cover plate is made from a material substantially not transparent to the wavelength of the optical signals emitted by the two sources  7 . 1  and  7 . 2 . Two optical beams of the diffused type  32 . 1  and  32 . 2 , emitted by the optical sources  7 . 1 ,  7 . 2 , starting from inside the chambers  16 . 1  and  16 . 2  cross the body  2  of the frame  1  to go out from the edge walls  2 . 1 ,  2 . 2  of the body  2  of the frame  1  and project onto a wall on which the frame, the electrical apparatuses and the plate are fixed. 
   It is possible to understand how a support frame in accordance with the present invention makes it particularly easy to locate the electrical apparatuses mounted at the support frame also without external lighting, creating, moreover, a pleasant aesthetic effect. 
   Of course, the man skilled in the art can mane numerous modifications and variations to the support frame described above, in order to satisfy contingent and specific requirements, all of which are in any case covered by the scope of protection of the invention as defined by the following claims.