Abstract:
An operating device for an electrical appliance with a control panel has a control element for operation through rotary actuation arranged in the control panel, said control element being disposed and mounted in a receptacle behind the control panel. The receptacle has light-conducting and/or light transmitting material in the manner of a light guide, and is illuminated through an LED at a posterior end facing away from the control panel and with light apertures provided at another anterior end on the control panel around the control element extending forwardly beyond the control panel.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to German Patent Application Number 10 2009 006 434.6, filed on Jan. 22, 2009, the contents of which are incorporated by reference. 
     FIELD OF THE INVENTION 
     The invention relates to an operating device for a household electrical appliance, as well as a corresponding control panel. 
     BACKGROUND OF THE INVENTION 
     Operating devices for household electrical appliances are known in numerous forms. The great majority of them, as known for instance from EP 1 318 534 A1, are receptacles arranged on, or behind, a control panel, and in which a control element, for instance a rotary knob, is mounted. This may be retractable under certain circumstances. A rotary switch device is arranged behind on the receptacle and is operated through the rotary knob. Openings may be provided in the control panel for optical display purposes, behind which LEDs or other lighting means are arranged. Through this, for instance, an operating state may be displayed on the operating device. 
     SUMMARY 
     An object of the invention is to create an operating device of the afore-mentioned type that has further functions and with which a simple construction can be advantageously achieved. 
     This object is met through an operating device as claimed herein, together with a corresponding control panel as claimed herein. Advantageous and preferred embodiments of the invention are the subject of further claims and are described in more detail below. The wording of the claims is made content of the description through express reference. 
     The control element is disposed in/contained in a receptacle behind the control panel. It can advantageously be mounted in it in such a way that it can rotate and also possibly be contained in one embodiment as a retractable control element. In accordance with an embodiment of the invention, the receptacle has light-conducting and/or light-transmitting material in the form of a light guide, and can therefore guide light. It is particularly advantageous if the receptacle substantially comprises such material. The receptacle is illuminated by lighting means at one posterior end facing away from the control panel, i.e., light is coupled into it. Light apertures are arranged at another anterior end of the receptacle on the control panel, especially around the control element or alternatively within the control element, so that light can exit from the front or is visible from the front. This enables, as a first function, the possibility that the receptacle accommodates the control element, or that the control element is mounted in the receptacle. The second function of the receptacle, since it is advantageously manufactured from a plastic, is to act as a light guide. This dispenses with the need for further openings in the control panel and only that opening is necessary in which the receptacle is anyway arranged. Further advantages are provided by the further advantageous embodiments described below. 
     In another embodiment of the invention, the receptacle has a plurality of light-conducting segments, or is subdivided into such segments, in a longitudinal direction and/or the light-conducting direction, i.e., from its posterior end, at which for instance a switching element, actuated through a control panel, is provided, in the direction of the anterior end. A subdivision is advantageously achieved through non-light-conducting segments or inserts and/or longitudinal sections. Then, depending on the arrangement of the light apertures at the front on the control panel, the light-conducting segments and/or sections may be smaller than the non-light-conducting ends or vice versa. The non-light-conducting segments and/or longitudinal sections are advantageously substantially smaller or narrower so that on the whole the greatest part of the receptacle serves as a light guide. Such non-light-conducting segments and/or longitudinal sections should be arranged for complete separation of neighbouring light-conducting longitudinal sections, and so to speak extend over the entire length of the receptacle from the posterior end to the anterior end. 
     The lighting means advantageously radiate light in the light-conducting direction and/or in the afore-mentioned longitudinal extension of the receptacle into it, or is arranged in such a way to it. 
     In a further advantageous embodiment of the invention, wherein the receptacle is subdivided into a plurality of segments and/or longitudinal sections, at least one lighting means is provided on each of the segments. The lighting means of different segments and/or longitudinal sections are then preferentially controllable independently of one another and may have different colours or generate different colours. It is thus possible that with, for example, four longitudinal sections of the receptacle four light apertures are formed on the anterior side of the operating device, which are then activated depending on state and possibly having different colours. If the length of the receptacle in the light-conducting direction differs, then it is sufficient, for instance, to have light from one lighting means for a somewhat uniform appearance of light at the light aperture. 
     The afore-mentioned receptacle with light-conducting and non-light-conducting regions can be advantageously manufactured through two-component injection moulding. Under certain circumstances, the same plastic may be used and is usually light-conducting and correspondingly coloured only for the non-light-conducting regions and/or subdivisions. An alternative manufacturing method is to group together a plurality of individual parts with light-conducting and non-light-conducting properties to form the receptacle, with the parts advantageously welded to one another or bonded through adhesive. 
     In another embodiment of the invention, the light apertures may be narrow and have a circular segment-like and/or circular form arranged around the control panel. This can lead, above all, to a functional state of the electrical appliance, to which the operating device belongs. 
     In an alternative embodiment of the invention, the light apertures can have a circular shape or circular segment shape, although with a considerable width. In particular, the width may be at least half the diameter of the control element so that all of the light apertures together may form a type of sleeve or wide ring around the control element on the control panel. This enables not only a lighting or optical display over a large area, but also, for example, through non-light-transmitting printing on the surface of such a wide-area light aperture a certain display of information, namely certain symbols or the like. 
     The receptacle advantageously has a somewhat cup-like shape, and can be in some embodiments, for instance, have a round and circumferentially shape of a section of pipe. It is open at the anterior end towards the control panel, and can advantageously have the afore-mentioned sleeve-like or collar-like form with extension outwardly to the side. It can be substantially closed to the posterior end and have only one opening for a shaft on which the control element sits on the one hand and possibly is secured to it and through which on the other hand a switching device is controlled or rotated. Such a shaft does not have to be continuous and can, for example, comprise several parts. In general, a control element, for instance a retractable rotary knob, can also comprise several parts, in particular to realise the retracting mechanism. 
     The switching device, which is operated through the control element, can be advantageously secured to the posterior end of the receptacle, in particular along the longitudinal direction of the receptacle. A possible constructive form of such a receptacle is described, for instance, in EP 1 318 534 A1, to which explicit reference is made here, also in respect of a possible mounting of the afore-mentioned shaft in the receptacle. The switching device can be secured to the receptacle through bolts, clips or the like. 
     In another advantageous embodiment of the invention, the operating device may be formed such that it can be inserted as a separate component in a control panel of an electrical appliance, or in a corresponding opening. For this the aforementioned light apertures or collar-like sections in particular can come to lie in corresponding recesses or cavities of the control panel, so that it remains flush on the anterior side. Wide collar-like sections on the receptacle also have the advantage that they enable mounting and/or securing of the receptacle to the control panel in a manner that is particularly stabile against tilting. 
     In an alternative embodiment the entire control panel together with the receptacle may be manufactured as a single part, for instance through multi-component injection moulding. 
     In a further embodiment of the invention, light-conducting means can be provided that extend from the receptacle into the control element and are guided to one anterior side or outer side of the control element. These light-conducting means can commence at the posterior end of the receptacle and have corresponding light-emitting means. Alternatively, they can radiate light from the side, for instance from the circular or collar-like sections described above, into the control element. So, for instance, a particular rotary position of the control element can be displayed. Such light-conducting means can also be integrated or injection moulded in the control element or in the receptacle, for instance as light-conducting regions, similarly to the way described above for the receptacle. 
     These and further characteristics are derived from the claims and also from the description and the drawings, and the individual characteristics either individually or together in the form of sub-combinations are realized in various embodiments of the invention and in other areas and can advantageously represent embodiments that are protectable in their own right and for which protection is claimed here. The division of the application into intermediate headings and individual sections does not limit the general validity of the statements made thereunder. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Example embodiments of the invention are shown schematically in the drawings and described in more detail below. The drawings are: 
         FIG. 1  illustrates a section through an operating device in a control panel with receptacle and switching device attached thereto, 
         FIG. 2  illustrates a top view of the operating device from  FIG. 1 , 
         FIG. 3  illustrates a side view of the operating device from  FIG. 1  in a non-cut state of the operating device, 
         FIG. 4  illustrates a representation similar to  FIG. 1  along the cut line C-C from  FIG. 2  and 
         FIG. 5  illustrates a further sectional view similar to  FIG. 4  with a receiving cup in a different form. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows an operating device  11  according to the invention, as it can be used on the anterior side in a control panel  12  of an electrical appliance, for instance an electric oven. The control panel  12  has a correspondingly formed recess  13  which, as shown in  FIG. 2  also, has a round and stepped form for flush insertion of the operating device  11  in the control panel  12 . 
     The operating device  11  has a rotary knob  15  as a control element. The rotary knob  15  has a grip part  16  that projects beyond the control panel  12  and which is mounted on a base part  17 . The operating device  11  and/or rotary knob  15  are in the form of retractable knobs so that, as shown in  FIGS. 3 and 4 , the grip part  16  can be displaced onto the base part  17  by pressing and then projects to only a very minor extent beyond the control panel  12 . The corresponding mechanism for this will be familiar to a person skilled in the art and does not need to be explained further. 
     The rotary knob  15  is mounted or fixed in a receiving cup  19 . The receiving cup  19  has an outer jacket  20  that is advantageously cylindrical and round circumferential, as well as a corresponding inner jacket  23 . The lower part of the grip part  16  or, substantially the entire grip part  16  corresponding to  FIG. 4 , is in the space between the outer jacket  20  and inner jacket  23 . The outer jacket  20  and inner jacket  23  are connected to each other, are advantageously a single part and in particular are manufactured at the same time and/or with one another. 
     To the front the receiving cup  19  or the outer jacket  20  has a collar-like extension  24 , which forms a circular ring. This can be seen in the top view in  FIG. 2 . The circular ring-like, collar-like extension  24  is divided into  4  fields of illumination  25   a  to  25   d . This is described in more detail below. 
     A rotary switch device  28  is secured to a posterior end  26  of the receiving cup  19  in a usual manner in accordance with the afore-mentioned EP 1 318 534 A1. The rotary switch device  28  also has the usual form, for instance in accordance with EP 1 898 184 A1. In particular it is a so-called Grey Code switch. 
     A support  29  is disposed on the rear-facing end  26  of the receiving cup as known from the afore-mentioned EP 1 318 534 A1. An axle stub  30  is mounted on this support  29  so that it can rotate, but is fixed in an axial direction. This axle stub  30  ensures transfer of the rotation from the grip part  16  to the rotary switch device  28 . 
     A lighting means  32   d  is arranged on the left and a lighting means  32   b  is arranged on the right in the rotary switch device  28 , especially LEDs. Reference is made to these in the aforementioned EP 1 898 184 A1, wherein the lighting means  32  either have the same control/same plug connection as the rotary switch device  28  or a separate one. 
     The light from the left lighting means  32   d  is coupled on the left into the outer jacket  20  of the receiving cup  19 . For this it comprises light-conducting material  21 , as well as the corresponding illuminated field  25   d . The inner jacket  23  can also comprise light-conducting material, but this is of secondary importance. 
     The largest part of the outer jacket  20  can be substantially of light-conducting material  21 . As is clearly seen in  FIG. 2 , both the outer jacket  20  and the illuminated fields  25   a  to  d  can be subdivided into four regions or sectors. This subdivision is formed through separating strips  22  of non-light-conducting material. These separating strips  22  may be manufactured as a single piece with the rest in the region of the collar-like extension  24 , in particular through two-component injection moulding. They can extend from the collar-like extension  24 , i.e., between the illuminated fields  25 , through the outer jacket  20  of the receiving cup  19  to the posterior end in front of the lighting means  32 . The separating strips  22  therefore bring about a division into four of the light-conducting material  21  as shown in  FIG. 2  in a direction in the drawing plane. A lighting means  32 , arranged behind each light-conducting region in accordance with section B-B, which can be seen in the sectional view in  FIG. 1 , sits approximately centrally when viewed in a circumferential direction and radiates light into one of the light guides formed so to speak as a result and which then exits frontally at the illuminated fields  25   a  to  25   d.    
     A greater or smaller number of divisions may be provided in place of the division into four shown here. A corresponding number of lighting means then has to be provided, wherein in a further development of the invention, more than one lighting means, for instance more than one LED, is provided per illuminated field  25 . 
     In the side view shown in  FIG. 3  it can be seen how two regions of the receiving cup  19  and/or its outer jacket  20  comprise light-conducting material  21 . They are, however, separated through a separating strip  22 , which also extends seamlessly through the collar-like extension  24  and therefore also separates the illuminated fields  25  from one another and prevents over-illumination. 
     In the sectional view shown in  FIG. 4  according to section A-A in  FIG. 2 , the cut goes directly through the plane of two separating strips  22 . This is also recognisable through the different hatching in the region of the separating strips  22  and on the outer jacket  20  as well as on the collar-like extension  24 . Furthermore, it can be seen that the separating strips  22  are also provided on the inner jacket  23  to bring about complete separation of adjoining circular ring segments. If the grip part  16 , however, is of non-light-transmitting material, then it does not matter if it is illuminated through the inner jacket  23  extending within it. 
     Through any desired control of the lighting means  32 , in principle also fully independently of whether the rotary knob  15  is pressed in or is in an out position, it is possible to control whether one or more of the illuminated fields  25   a  to  25   d  is illuminated. As already described, some of the lighting means  32  can be coloured, so that the illuminated fields  25  may be illuminated in different colours. 
     Whilst the afore-mentioned two-component injection moulding is the preferred manufacturing method for such a receiving cup  19 , of corresponding light-conducting material  21  with separating strips  22  in between, other possibilities are also conceivable. For instance, a plurality of parts of the same type can be grouped together to form a receiving cup  19 , with possible interspersion of non-light-conducting layers or parts. Alternatively, for instance, laser irradiation of the receiving cup manufactured from actual light-conducting material along the separating strips could change it such that light is no longer conducted here or that sectors so to speak can no longer be overcome. 
     The spring  34 , recognisable in the sectional views, of metal and connected to a metal button disposed on the anterior side of the grip part  16 , can be electrically contacted through an axle stub  30  that is also electrically conducting. This enables a capacitive touch switch to be created in accordance with US 2007/0181410 A1. 
     Reference is also drawn to the German patent application DE 102009006421.4 lodged at the same priority date by the same applicant. 
     An alternative operating device  111  is shown in  FIG. 5 , in which a rotary knob  115  is again disposed in a control panel  112  or cut-out section  113 . This rotary knob  115  is also in the form of a rotary retractable knob and is only shown in a retracted state, a grip part  116  is therefore pushed onto a base part  117 . 
     The receiving cup  119  here is without a collar-like extension as before, and instead has only its front face  137  in the cut-out section  113 . This yields, through the front face  137 , a narrow ring that encircles the grip part  116 . A collar-like extension  124  is displaced a little downwardly and serves to secure the receiving cup  119  in a stabile and non-tiltable manner to the control panel  112 . It cannot, however, be seen from the front. 
     It can also be seen that an outer jacket  120 , that becomes the afore-mentioned collar-like extension  124 , is substantially of pipe section form and is not manufactured as a single part with an inner jacket  123  of the receiving cup  119 , but instead is disposed on top of it and is advantageously connected to it or bonded to it. Here too, a rear-facing end  126  of the receiving cup  119 , in this case within the outer jacket  120 , is connected to a rotary switch device  128 . An axle stub  130  is mounted in a support  129  and in turn engages in the base part  117  of the rotary knob  115 . In addition, it should further be noted that the rotary switch device  128  is disposed on a circuit board  131  and in particular is also electrically connected. The circuit board  131  also bears lighting means  132 , advantageously in the form of LEDs and/or SMD LEDs. 
     Not shown in  FIG. 5  are corresponding separating strips between the light-conducting material, which substantially forms the outer jacket  120  and the inner jacket  123 . This can, however, have a form analogous to the previous embodiments. 
     Above all, however, it is possible or envisaged with an operating device  111  according to  FIG. 5  for the outer jacket  120  and inner jacket  123  of the receiving cup  119  to be connected to one another in a non-light-conducting manner, and for this reason different lighting means  132  are provided. They can be separated by a coating or intermediate layers. So, for instance, the coupling of light into the outer jacket  120  can bring about a narrow, circular segment-like light appearance at the front faces  137  on the control panel  112 , with a division that embraces a 90° elbow angle similar to  FIG. 2 , or less or more. The illumination of the inner jacket  123  can be used to create an optical display through lights on the anterior side of the grip part  116 . For this the anterior side of the grip part  116  can be formed from corresponding light-transmitting material. So, for example, different functional states of the operating device  111  can also be shown on the rotary knob  115 . Illumination of the knob on the one hand or the control panel on the other hand can, in line with the general concept of the invention, be achieved together or only individually. Above all, different illuminations and different colours can thus be generated. 
     Furthermore, a segmentation of the inner jacket  123  and outer jacket  120  through corresponding separating strips can be different, in particular through angular displacement, relative to one another. This enables any desired illuminated representation to be achieved.