Patent Publication Number: US-2009229475-A1

Title: Cooking appliance

Description:
The present invention relates to a cooking appliance, in particular a high-level cooking appliance, having at least one muffle which delimits a cooking compartment and has a muffle opening, a door for closing the muffle opening, said door being movable by means of a drive device, and a control circuit for controlling the drive device. 
     Prior art high-level cooking appliances are known in which a base door can be caused to move in the desired direction by actuation of a corresponding travel button. 
     DE 101 64 239 A1, for example, discloses a generic high-level cooking appliance in which a control device controls the travel movement of a base door. 
     A disadvantage is that a simple door travel movement control of this kind affords no protection whatever against a malfunction of the control device and, with the exception of the pinching instance, also provides no further protective measures for the operator. 
     The object of the present invention is therefore to provide a cooking appliance, in particular a high-level cooking appliance, having improved operational safety during the travel movement of the base door. 
     The present object is achieved by means of the cooking appliance having the features recited in claim  1  and by means of a method as claimed in claim  18 . 
     With that object in view, the cooking appliance, which is in particular a high-level cooking appliance but may also be a cooking appliance having a baking carriage, is designed in such a way that the door is only movable when at least one safety signal is present, which is to say a signal which activates specific functionalities by hardware or software means. Without the safety signal being present, no travel movement of the door is possible even when the travel switches are operated correctly. The safety signal is usually output by at least one processor unit, typically a microcontroller, in a defined manner, which is possible only if the device electronics or the electronics used for controlling the door&#39;s travel movement are in a proper condition. The safety signal can also be used to ensure compliance with further security conditions. 
     To provide an improved safeguard against unintentional travel movement, the door can beneficially be moved only if two safety signals are present together. 
     It is advantageous in particular if at least one of the safety signals is present or is generated only if a temperature of the closed cooking compartment is below a temperature threshold value, specifically if the temperature threshold value is 600° F. or 425° C. This can serve to prevent a user burning himself/herself on a part of the oven or on a dish that is too hot. It is equally advantageous if, in addition or alternatively, at least one of the safety signals is present only when a child safety device is not activated. By this means an unintentional travel movement triggered by children can be prevented. 
     It is also favorable if the safety signals are pulsed signals, in particular square wave signals, since in this way, when microcontrollers are used, their correct operation is ensured. 
     It is furthermore advantageous if a voltage supply for the drive device can additionally be switched on by means of one of the safety signals, since this results in a dual safety function (switching on/activation of the drive device). 
     It is advantageous for a safe, reliable and flexible design if the control circuit includes at least one lift board for actuating the drive device and a regulator board for controlling, switching and/or regulating the lift board. 
     Advantageously, a first, internal safety signal is generated by the lift board and a second, external safety signal is generated by the regulator board. The internal safety signal is preferably generated by the lift board in response to a travel movement signal S 3 , e.g. an actuation of a travel switch panel  25 ,  26  or a travel command of an automatic program. The external safety signal is favorably generated by the regulator board only at the request of the lift board. The regulator board is preferably connected to a temperature sensor for monitoring a temperature of the cooking compartment and/or to a child safety device in order thereby to control the corresponding activation/deactivation capability of the external safety signal. For this purpose a hardware-implemented circuit for deactivating the external safety signal is favorably present which is switchable in particular by means of signals from the temperature sensor and/or the child safety device, e.g. by means of a safety relay. However, the activation/deactivation capability can also be ensured by means of a computer program product for deactivating the external safety signal, which computer program product can likewise be controlled in particular by means of signals from the temperature sensor and/or the child safety device. 
     It is also advantageous if the drive device includes a drive motor which can be activated by means of directional relays which in turn are switchable in each case by means of at least one transistor, since transistors are particularly easy, quick and cheap to switch by means of control signals. 
     A typical application scenario comprises the following steps:
     (a) generating a travel movement starting signal, in particular by actuating at least one travel switch panel;   (b) receiving the travel movement starting signal at the lift board;   (c) generating an internal safety signal on the lift board;   (d) requesting an external safety signal from the regulator board by the lift board;   (e) generating an external safety signal on the regulator board if no lock is present;   (f) if no lock is present, outputting the external safety signal to the lift board and to a voltage supply for the drive device;   (g) operating the drive device in the desired direction by means of the lift board, provided both the internal safety signal and the external safety signal are present.   

     To simplify operator control, the drive device can advantageously be operated by actuating both travel switch panels even if the main switch is switched off. 
    
    
     
       The invention is described in greater detail below with reference to the attached schematic figures, in which: 
         FIG. 1  shows a perspective view of a high-level cooking appliance which is mounted on a wall and has a lowered base door; 
         FIG. 2  shows a perspective view of the high-level cooking appliance with closed base door; 
         FIG. 3  shows a perspective view of a housing of the high-level cooking appliance without the base door; 
         FIG. 4  shows a schematic side view, in cross section along the line I-I from  FIG. 1 , of the high-level cooking appliance which is mounted on the wall and has a lowered base door; 
         FIG. 5  shows a front view of a further embodiment of a high-level cooking appliance; 
         FIG. 6  is a schematic showing a layout of a control circuit in relation to a travel movement of the base door. 
     
    
    
       FIG. 1  shows a high-level cooking appliance with a housing  1 . The rear side of the housing  1  is mounted on a wall  2  in the manner of a suspended cabinet. A cooking compartment  3 , which can be monitored via a viewing window  4  installed in the front side of the housing  1 , is defined in the housing  1 . It can be seen from  FIG. 4  that the cooking compartment  3  is delimited by a muffle  5  which is equipped with a heat-insulating jacket (not shown) and that the muffle  5  has a base-side muffle opening  6 . The muffle opening  6  can be closed by means of a base door  7 . The base door  7  is shown lowered in  FIG. 1 , wherein its underside is in contact with a work surface  8  of a kitchen entity. In order to close the cooking compartment  3 , the base door  7  must be repositioned to the position shown in  FIG. 2 , the so-called “zero position”. For the purpose of repositioning the base door  7 , the high-level cooking appliance has a drive device  9 ,  10 . The drive device  9 ,  10  has a drive motor  9  which is illustrated by means of broken lines in  FIGS. 1 ,  2  and  4  and is arranged between the muffle  5  and an external wall of the housing  1 . The drive motor  9  is arranged in the region of the rear side of the housing  1  and, as shown in  FIG. 1  or  4 , has an active connection to a pair of lifting elements  10  which are connected to the base door  7 . In this case, as shown in the schematic side view in  FIG. 4 , each lifting element  10  is designed in the form of an L-shaped carrier whose vertical limb extends from the drive motor  9  in the housing. For the purpose of repositioning the base door  7 , the drive motor  9  can be actuated with the aid of an operating panel  12 , which is arranged on the front of the base door  7  in accordance with  FIGS. 1 and 2 , and a control circuit  13 . As shown in  FIG. 4 , the control circuit  13  is located behind the operating panel  12  within the base door  7 . The control circuit  13 , which is composed of a plurality of spatially and functionally separate printed circuit boards that communicate via a communication bus, represents a central control unit for the appliance operation and controls and/or adjusts e.g. heating, travel of the base door  3 , conversion of user inputs, lighting, pinching protection, timing of heating elements  16 ,  17 ,  18 ,  22  and much more. 
     It can be seen from  FIG. 1  that a top side of the base door  7  has a cooking matrix  15 . Almost the entire surface of the cooking matrix  15  is occupied by heating elements  16 ,  17 ,  18 , these being indicated in  FIG. 1  by dash-dotted lines. In  FIG. 1 , the heating elements  16 ,  17  are two separate cooking position heating elements of different sizes, while the heating element  18  is a surface heating element which is provided between the two cooking position heating elements  16 ,  17  and almost surrounds the cooking position heating elements  16 ,  17 . The cooking position heating elements  16 ,  17  define associated cooking zones or cooking rings for the user; the cooking position heating elements  16 ,  17  and the surface heating element  18  together define an underside-heating zone. The zones can be indicated by means of a suitable motif on the surface. The heating elements  16 ,  17 ,  18  can be controlled in each case via the control circuit  13 . 
     In the exemplary embodiment shown, the heating elements  16 ,  17 ,  18  are embodied as radiant heating elements which are covered by a glass ceramic plate  19 . The glass ceramic plate  19  has approximately the dimensions of the top of the base door  7 . The glass ceramic plate  19  is also equipped with mounting openings (not shown), through which sockets project for the purpose of holding support parts  20  for cooking item carriers  21 , as is also shown in  FIG. 4 . Instead of a glass ceramic plate  19 , it is also possible to use other—preferably quick-reacting—covers, e.g. thin sheet metal. 
     With the aid of an operating knob which is provided in the operating panel  12 , the high-level cooking appliance can be switched to a cooking position operating mode or an underside-heating operating mode, wherein these are explained below. 
     In the cooking position operating mode, the cooking position heating elements  16 ,  17  can be controlled individually via the control circuit  13  by means of operating elements  11  which are provided in the operating panel  12 , while the surface heating element  18  remains unused. The cooking position operating mode can be implemented when the base door  7  is lowered as shown in  FIG. 1 . However, it can also be operated in an energy-saving function when the cooking compartment  3  is closed and the base door  7  is raised. 
     In the underside-heating operating mode, the control device  13  controls not only the cooking position heating elements  16 ,  17  but also the surface heating element  18 . 
     In order to achieve a maximally even browning impression of the cooking item during the underside-heating operation, it is critical that the cooking matrix  15  which provides the underside heating exhibits an even distribution of the heat power output over the surface of the cooking matrix  15 , even though the heating elements  16 ,  17 ,  18  have different nominal powers. Therefore the heating elements  16 ,  17 ,  18  are preferably not switched to a continuous operation by the control circuit  13 , but the current supply to the heating elements  16 ,  17 ,  18  is timed. In this case, the different nominal heating powers of the heating elements  16 ,  17 ,  18  are reduced individually in such a way that the heating elements  16 ,  17 ,  18  provide an equal distribution of the heating power output over the surface of the cooking matrix  15 . 
       FIG. 4  schematically shows the position of a fan  23 , e.g. for the generation of recirculating air in the case of hot air operation or for supplying fresh air. Furthermore, provision is made for a topside-heating element  22  which is attached at a top side of the muffle  5  and can be embodied as a single circuit or multiple circuit, e.g. having an inner circuit and an outer circuit. It is also possible—not shown here for the sake of greater clarity—to provide for further heating elements such as a ring heating element between a rear wall of the housing  1  and the muffle. The different operating modes including e.g. topside-heating operation, hot-air operation or rapid-heating operation can be set by the control circuit  13  by switching on and setting the heating power of the heating elements  16 ,  17 ,  18 ,  22  correspondingly, optionally with activation of the fan  23 . The setting of the heating power can be done by means of suitable timing. In addition, the cooking matrix  15  can be embodied differently, e.g. with or without a grilling zone, as a simple heat-retention zone (featuring a single circuit or multiple circuits) without cooking rings, etc. The housing  1  has a seal  24  which faces the base door  7 . The operating panel  12  is normally arranged on the front side of the base door  7 . Alternatively, other arrangements are also conceivable, e.g. on the front side of the housing  1 , divided over various partial panels and/or partly on side surfaces of the cooking appliance. Further configurations are possible. The operating elements  11  are not restricted in terms of their construction, and can comprise e.g. operating knobs, tumbler switches, pushbuttons and plastic membrane buttons. The display elements  14  comprise e.g. LED, LCD and/or touchscreen displays. 
       FIG. 5  schematically shows a high-level cooking appliance from the front (not to scale), wherein the base door  7  is open and is in contact with the work surface  8 . The closed state is drawn by means of a broken line. 
     In this embodiment there are two travel switch panels  25  on the front side of the permanently attached housing  1 . Each travel switch panel  25  comprises two pushbuttons, specifically an upper CLOSE pushbutton  25   a  which causes a base door  7  to travel upward in a closing direction, and a lower OPEN pushbutton  25   b  which causes a base door  7  to travel downward in an opening direction. Without automatic operation (see below) the base door  7  only travels upward as a result of continuous simultaneous depression of the CLOSE buttons  25   a  of both travel switch panels  25 , if possible; the base door  7  also only travels downward as a result of continuous simultaneous depression of the OPEN buttons  25   b  of both travel switch panels  25 , if possible (manual operation). Since increased operating alertness on the part of the user is assumed in the case of manual operation, and both hands are also used here, pinching protection is only optional. In the case of an alternative embodiment, travel switch panels  26  are attached on opposite external sides of the housing  1  and have corresponding CLOSE buttons  26   a  and OPEN buttons  26   b , as drawn using dotted lines. 
     The control circuit  13 , which is drawn using dash-dotted lines and is located in the interior of the base door  7  behind the operating panel  12 , switches the drive motor  9  in such a way that the base door  7  begins to move gently, i.e. not abruptly by simply starting the drive motor  9 , but by means of a defined ramp. 
     In this exemplary embodiment, the control circuit  13  comprises a memory unit  27  for storing at least a destination or travel position P 0 , P 1 , P 2 , PZ of the base door  7 , preferably using volatile memory modules, e.g. DRAMs. If a destination position P 0 , P 1 , P 2 , PZ is stored, following actuation of one of the buttons  25   a ,  25   b  or  26   a ,  26   b  of the travel switch panels  25  or  26 , the base door can travel independently in the selected direction until the next destination position has been reached or until one of the buttons  25   a ,  25   b  or  26   a ,  26   b  is actuated again (automatic operation). In this exemplary embodiment, the lowermost destination position PZ corresponds to the maximum opening, the (zero) position P 0  corresponds to the closed state, and P 1  and P 2  are freely selectable intermediate positions. If the last destination position for a direction has been reached, manual operation is additionally necessary for further travel, if possible (i.e. if the last final positions do not correspond to a maximally open final state or to the closed final state). Similarly, if no destination position is stored for a direction (which would be the case e.g. for an upward movement into the closed position if only PZ is stored but not P 0 , P 1 , P 2 ), movement in this direction requires manual operation. If no destination position is stored, e.g. in the case of a new installation or following a power disconnection, no automatic operation is possible. If the base door  7  is to travel using the automatic operation, pinching protection is preferably activated. 
     Automatic operation and manual operation are not mutually exclusive: as a result of continuous actuation of the travel switch panel(s)  25 ,  26 , the base door  7  also moves in manual operation if a destination position is nonetheless available in this direction. In this case, it is possible to define e.g. a maximum actuation time of the travel panels  25  or  26 , or of the associated buttons  25   a ,  25   b  and  26   a ,  26   b  respectively, for the purpose of activating the automatic operation, e.g. 0.4 seconds. 
     A destination position P 0 , P 1 , P 2 , PZ can be any desired position of the base door  7  between and including the zero position P 0  and the maximum opening position PZ. However, the maximum stored opening position PZ does not have to be the position which is in contact with the work surface  8 . Storage of the destination position P 0 , P 1 , P 2 , PZ can be carried out with the base door  7  at the desired destination position P 0 , P 1 , P 2 , PZ by means of e.g. actuating a confirmation button  28  in the operating panel  12  for several seconds (e.g. two seconds). For the sake of greater clarity, available optical and/or acoustic signal emitters which output corresponding signals following storage of a destination position are not drawn. Arriving at the desired destination position P 0 , P 1 , P 2 , PZ to be set is achieved e.g. by means of—in this exemplary embodiment—two-handed operation of the travel switch panels  25  or  26  and manual travel to this position. 
     It is possible to store just one or, as shown in this exemplary embodiment, also a plurality of destination positions P 0 , P 1 , P 2 , PZ in the memory unit  27 . In the case of a plurality of destination positions P 0 , P 1 , P 2 , PZ, these can be reached successively by actuating the corresponding travel buttons  25   a ,  25   b  or  26   a ,  26   b . By virtue of a plurality of destination positions P 0 , P 1 , P 2 , PZ, the high-level cooking appliance can easily be adjusted to the desired operating height of a plurality of users. The destination position(s) can advantageously be deleted and/or overwritten. In one embodiment, for example, only one destination position in the open state can be stored, while the zero position P 0  is detected automatically and can be reached automatically. Alternatively, the zero position P 0  must also be stored in order that it can be reached automatically. 
     For ergonomic use it is particularly advantageous if the or a destination position P 1 , P 2 , PZ opens the base door  7  at least approximately 400 mm to approximately 540 mm (i.e. P 1 -P 0 , P 2 -P 0 , PZ-P 0 ≧40 cm to 54 cm). At this opening distance, the cooking item carriers  21  can easily be inserted into the support parts  20 . In this case, it is advantageous if the viewing window  4  is mounted at approximately eye level of the user or somewhat lower, e.g. by means of a template which indicates the dimensions of the cooking appliance. 
     A power failure protection for bridging power outages lasting approximately 1 to 3 s, preferably up to 1.5 s, is present but not illustrated. 
     The drive motor  9  from  FIG. 1  has at least one sensor unit  31 ,  32  on a motor shaft  30 , these being arranged before or after a transmission if applicable, in order to measure a travel displacement or a position and/or a speed of the base door  7 . The sensor unit can comprise e.g. one or more induction sensors, Hall-effect sensors, optoelectronic sensors, SAW sensors, etc. In this case, in order to measure displacement and speed in a simple manner, two Hall-effect (partial) elements  31  are attached to the motor shaft  30  such that they are offset by 180°—i.e. opposite each other—and a Hall-effect measurement pick-up 32 is separately attached in a fixed manner in this region of the motor shaft. When a Hall-effect element  31  then travels past the measurement pick-up 32 as the motor shaft  30  rotates, a measurement signal or sensor signal is generated which is closely approximate to digital. Using (not necessarily) two Hall-effect elements  31 , therefore, two signals are output with one rotation of the motor shaft  30 . By analyzing these signals relative to time, e.g. their time difference, it is possible to determine the speed vL of the base door  7 , e.g. using comparison tables or a real-time conversion in the control circuit  13 . By means of adding or subtracting the measurement signals, it is possible to determine a travel displacement or a position of the base door  7 . 
     A speed regulator can realize the speed e.g. via a PWM-controlled power semiconductor. 
     In order to determine the zero point, the displacement measurement is automatically reset by initializing in the zero position P 0  of the base door  7  at each start-up, in order that e.g. an erroneous sensor signal output or sensor signal pick-up is not perpetuated. 
     The drive motor  9  can be operated by actuating both travel switch panels  25  or  26  even if the main switch  29  is switched off. 
     Instead of two separate switches per travel panel  25 ,  26 , a single switch per travel panel is also possible, e.g. a tumbler switch which has a neutral position and only switches under pressure. Other forms are also possible. The type and arrangement of the operating elements  28 ,  29  of the operating panel  12  are likewise not restricted. 
     The arrangement and distribution of the control circuit  13  is flexible and not restricted in this case, and can therefore comprise a plurality of boards, e.g. a display board, a control board and a lift board, which are physically separate. 
     A 4-mm opening can be detected by stop switches  33  which, when actuated, deactivate a pinching protection. 
     The high-level cooking appliance can also be embodied without a memory unit  27 , in which case no automatic operation is then possible. This can be suitable for increased operating safety, e.g. as protection against pinching. 
       FIG. 6  shows a schematic circuit diagram of the control circuit  13  connected to the drive motor  9 . The control circuit  13  consists in this case of three separate boards or modules, specifically a lift board  34  for directly actuating the drive motor  9 , a regulator board  35  for, inter alia, switching and/or regulating the lift board  34 , and a display board  36  for controlling the operating panel  12 , e.g. the display unit  14 , and processing and/or forwarding actuation signals of the operating elements  11 . The boards  34 - 36  are connected to one another for communication purposes via a DII bus line  37 ; the boards  34 - 36  can therefore also be arranged at different positions in the cooking appliance, e.g. the display board  36  behind the operating panel  12 , the regulator board  35  in the stationary part of the housing  1 , and the lift board  34  in proximity to the drive motor  9 . 
     The direction of the travel movement of the drive motor  9  and consequently of the base door  3  is determined by two relays (not shown in the figure) which are controlled by means of transistors. If one of the relays is active, the drive motor  9  travels in the assigned direction. If both relays are active—something which should be prevented under normal conditions—the drive motor  9  blocks. If no relay is active, the motor  9  is short-circuited and no travel movement is possible (idle state). In this exemplary embodiment the motor  9  can only be driven if at least two safety signals are present; which is to say in this case that only then can the transistors be triggered accordingly. A first safety signal is a(n) (internal) safety signal S 1  which is generated by the lift board  34  itself and is generated e.g. upon correct actuation of the travel movement or lift function, for example by actuation of the travel switches  25   a ,  25   b ,  26   a ,  26   b . The first safety signal S 1  ensures that a travel movement signal is correctly received and processed on the lift board  34 —i.e. that no error-induced switching of the relays by the lift board  34  is present—as otherwise the circuit for the safety signal, typically a microcontroller, would not trigger. Accordingly, this safety signal S 1  includes that the lift board electronics are basically operating correctly. The second safety signal is a(n) (external) safety signal S 2  which is generated by the regulator board  35  and typically takes into account further states managed by the regulator board  35 , e.g. a temperature in the closed cooking compartment  3  or an activation of a child safety device  40 . In this embodiment the external safety signal S 2  produces a dual activation: firstly the voltage supply for the relays and secondly, in conjunction with the internal safety signal S 1 , the corresponding transistor. In this exemplary embodiment the safety signals S 1 , S 2  are pulse signals (“wiggler signals”), more precisely: square wave signals, clocked at 1 KHz, which is advantageous, since most available microcontrollers must operate correctly for this. 
     A typical sequence of an actuation of the drive motor  9  takes place as follows: a user wishes to open a closed cooking compartment  3  containing a prepared dish in order to remove said dish. For that purpose he/she briefly, i.e. for less than 0.4 seconds, presses one of the “OPEN” buttons  25   b  in the automatic mode of operation. The actuation of the “OPEN” button  25   b  is sensed by the display board  36  and in this exemplary embodiment is forwarded via the signal bus  37  to the lift board; alternatively the actuation signal S 3  can be routed via a direct line to the lift board  34 . The lift board  34  detects the correct actuation signal S 3  and generates the internal safety signal S 1 . In addition, the lift board  34  now requests the external safety signal S 2  from the regulator board  35  via the bus  37 . The regulator board  35  checks whether any further conditions oppose a transmission of the external safety signal S 2 ; thus, a check is made to verify firstly whether the child safety device  40  is switched off and secondly whether a temperature sensor  39  indicates a temperature in the cooking compartment  3  that is lower than a temperature threshold value of e.g. 425° C. or 600° F. The external safety signal S 2  is output only if there are no further opposing conditions. In this embodiment the corresponding transistor and hence the corresponding directional relay are only triggered via a control line  38  if both the internal safety signal S 1  and the external safety signal S 2  are present. By means of the external safety signal S 2  the voltage supply for the relays is activated in addition by switching-on of the transformer  41  for the drive motor  9 . Only then can the drive motor  9  be actuated, and the base door  3  executes a travel movement accordingly. The external safety signal S 2  thus has a dual safety function. Alternatively, however, the external safety signal S 2  may also have only one of these functionalities. Furthermore, before the travel movement of base door  7  is initiated, both relays are additionally checked to verify their functionality. 
     The regulator board  35  uses a temperature measurement output by the temperature sensor  39 , e.g. a Pt500 or Pt1000 temperature sensor, to check, for example, whether the cooking compartment  3  is too hot to be opened. If the temperature is above a certain temperature threshold value, e.g. 415° C. or 600° F., the regulator board  35  does not output an external safety signal and the travel movement of the base door  7  is not triggered (locking). This locking or, as the case may be, deactivation of the external safety square wave signal S 2  can be effected by way of a hardware circuit, e.g. in such a way that if the temperature threshold value is exceeded, a switch required for switching the external safety signal S 2  is forced to open or remains open. Alternatively the lock can also be applied under program control. 
     The control circuit  13  may also be subdivided differently or not be subdivided at all. Obviously, the type and arrangement of the circuitry and signal controller are also not limited to the exemplary embodiment described. Furthermore, more or fewer than two safety signals may be used, e.g. only safety signal S 1  or S 2 , since even just one safety signal provides increased functional safety when travel movements are executed. It is also possible that further safety conditions are to be complied with during travel movements of the door. 
     LIST OF REFERENCE SIGNS 
     
         
           1  Housing 
           2  Wall 
           3  Cooking compartment 
           4  Viewing window 
           5  Muffle 
           6  Muffle opening 
           7  Base door 
           8  Work surface 
           9  Drive motor 
           10  Lifting element 
           11  Operating element 
           12  Operating panel 
           13  Control circuit 
           14  Display elements 
           15  Cooking matrix 
           16  Cooking position heating element 
           17  Cooking position heating element 
           18  Surface heating element 
           19  Glass ceramic plate 
           20  Support part 
           21  Cooking item carrier 
           22  Top heating element 
           23  Fan 
           24  Seal 
           25  Travel switch panel 
           25   a  Travel switch upward 
           25   b  Travel switch downward 
           26  Travel switch panel 
           26   a  Travel switch upward 
           26   b  Travel switch downward 
           27  Memory unit 
           28  Confirmation button 
           29  Main switch 
           30  Motor shaft 
           31  Hall-effect element 
           32  Measurement pick-up 
           33  Stop switch 
           34  Lift board 
           35  Regulator board 
           36  Display board 
           37  Bus line 
           38  Control line 
           39  Temperature sensor 
           40  Child safety device 
           41  Transformer 
         FT 1  First force/time profile 
         FT 2  Second force/time profile 
         P 0  Zero position 
         P 1  Intermediate position 
         P 2  Intermediate position 
         PZ Final position 
         R 1  Speed ramp 
         R 2  Speed ramp 
         S 1  Internal safety signal 
         S 2  External safety signal 
         S 3  Travel movement signal 
         vL Travel speed of the base door