Abstract:
In order to simplify and reduce the production costs of a push-button switch, especially a push switch or a rocker switch, the switch has a time function, which is manually operated and can be reset by an electric pulse. The electromechanical rocker or push-button switch can be combined to form a device block switch with other rocker or push-button switches as usually used in exhauster hoods. As a result, time-controlled intensive and follow-up steps can be carried out.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This application is a continuation, under 35 U.S.C. § 120, of copending international application No. PCT/EP02/13457, filed Nov. 28, 2002, which designated the United States; this application also claims the priority, under 35 U.S.C. § 119, of German patent application No. 101 63 193.6, filed Dec. 21, 2001; the prior applications are herewith incorporated by reference in their entirety. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    Field of the Invention  
           [0003]    The present invention relates to a switching apparatus for controlling devices having at least one mechanical momentary-contact switch for mechanically switching a functionality of a device. In particular, the present invention relates to a switching apparatus for controlling the intensive stages of an extractor hood.  
           [0004]    U.S. Pat. No. 5,690,093 A1 discloses an extractor hood having an electronic control system. The control device contains a microprocessor that drives the fan motor accordingly. The desired functions are input by a keypad. In addition to a number of pushbutton momentary contacts for various intensive stages, a pushbutton momentary contact is also provided for causing the extractor hood to continuously run. However, the pushbutton momentary contacts only act as pulse generators for the microprocessor. Purely electronic momentary-contact control is therefore provided. The manufacturing costs of electronic momentary-contact control systems of this type are relatively high.  
           [0005]    Published, Non-Prosecuted German Patent Application DE 198 02 332 A1 discloses an electrical rocker switch in which a moveable contact part bridges stationary contacts. The moveable contact part is loaded by a spring toward one switched position and, in the other switched position, by a magnet that is in the form of a permanent magnet. The magnetic field of the permanent magnet can be influenced by the magnetic field of an electromagnet such that the moveable contact part, which is held in a prestressed state, is moved into its other switched position when the magnetic field of the electromagnet is built up.  
         SUMMARY OF THE INVENTION  
         [0006]    It is accordingly an object of the invention to provide an electromechanical momentary-contact switch having timed supplementary functions that overcomes the above-mentioned disadvantages of the prior art devices of this general type, which has more favorable manufacturing costs and with which a device can be controlled.  
           [0007]    With the foregoing and other objects in view there is provided, in accordance with the invention, a switching apparatus for controlling a device. The switching apparatus contains at least one mechanical pushbutton momentary-contact switch for mechanically switching a functionality of the device. The mechanical pushbutton momentary-contact switch can be operated manually and can be reset by an electrical pulse.  
           [0008]    Furthermore, the above object is achieved by a switching apparatus for controlling devices having a plurality of mechanical momentary-contact switches, in particular rocker switches, for mechanically switching a plurality of functionalities of a device. At least one of the mechanical momentary-contact switches is capable of being operated manually and is reset by an electrical pulse.  
           [0009]    The advantage of the switching apparatus according to the present invention is that a mechanical pushbutton momentary-contact switch or a momentary-contact switch combination with a timing function can be embodied, as a result of which significant cost advantages in comparison with purely electronic solutions from the prior art are obtained. Such a rocker switch or pushbutton momentary-contact switch with a timing function can be combined with further rocker switches or pushbutton momentary-contact switches and other switches to form a switch block for domestic appliances, air-conditioning units, ventilation units, miniature devices and the like.  
           [0010]    Further advantages are that no standby-operating mode is necessary for the electromechanical momentary-contact switch according to the invention since the switch can always be actuated mechanically. As a result, the considerable consumption of energy for the standby mode can be dispensed with.  
           [0011]    The electromechanical momentary-contact switch is also significantly less susceptible to faults than purely electronic pressure switches. In particular, the mechanical rocker switch or pushbutton momentary-contact switch can be confirmed to have a significantly higher electromagnetic compatibility with respect to electromagnetic interference.  
           [0012]    In addition, the device that is to be actuated can be isolated clearly from the power supply system using the electromechanical momentary-contact switch. This is advantageous not only from a safety point of view but also for the configuration of further electronic components of the device.  
           [0013]    Other features which are considered as characteristic for the invention are set forth in the appended claims.  
           [0014]    Although the invention is illustrated and described herein as embodied in an electromechanical momentary-contact switch having timed supplementary functions, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.  
           [0015]    The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]    [0016]FIG. 1 is a diagrammatic, illustration of an embodiment of an electromechanical pushbutton momentary-contact switch according to the invention;  
         [0017]    [0017]FIG. 2 is a diagrammatic, front view of a switching apparatus having a plurality of pushbutton momentary-contact switches;  
         [0018]    [0018]FIG. 3 is a diagrammatic, front view of a variant of the switching apparatus according to FIG. 2;  
         [0019]    [0019]FIGS. 4A to  4 D are diagrammatic, perspective views of switched states of a quadruple rocker switch according to the invention;  
         [0020]    [0020]FIGS. 5A to  5 D are diagrammatic, perspective views of switched states of a quintuple rocker switch according to the invention; and  
         [0021]    [0021]FIGS. 6A and 6B are diagrammatic, perspective views of the switch in FIGS. 5A to  5 D from below. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    Referring now to the figures of the drawing in detail and first, particularly, to FIG. 1 thereof, there is shown a pushbutton momentary-contact switch which is held in the switched-on state after activation and can be switched off by an electrical pulse after a desired time interval. A momentary-contact element  1  is held in a sprung fashion against a housing  3 , which is illustrated only in its basic form, by a helical spring  2 . An electrical contact element  4  is attached to that end of the momentary-contact element  1  that lies opposite a contact surface. An electrical opposing contact  5  lies opposite the electrical contact element  4  in the direction of movement of the momentary-contact switch and is disposed on one side of a core of an electromagnet  6 . A permanent magnet  7  is located at the other end of the core of the electromagnet  6 .  
         [0023]    If the momentary-contact switch is then activated manually, the electrical contact between the contact elements  4  and  5  closes so that the momentary-contact switch is in an electrical ON state. The pushbutton momentary-contact switch then stays in the ON state since the electrical contact element  4  is held by the permanent magnet  7  over the core of the electromagnet  6  counter to the spring force of the spring  2 .  
         [0024]    In order to switch the pushbutton momentary-contact switch into the OFF state, a short pulse is applied to the electro-magnet  6 . The electrical pulse is in this case oriented such that its magnetic field induced in the coil of the electromagnet  6  counteracts the magnetic field of the permanent magnet  7 . As a result, the magnetic force exerted on the electrical contact element  4  is reduced, so that the spring  2  pushes the momentary-contact element  1  upward, opens the electrical contact and thus moves the pushbutton momentary-contact switch into the OFF state.  
         [0025]    The electrical pulse for the electromagnet  6  may be a control pulse from a non-illustrated control device, in particular the pulse of a time-delay switching element.  
         [0026]    [0026]FIG. 2 shows a schematic illustration of a front view of a control element of an extractor (exhaust) hood. All of the switches  8  to  13  are embodied as pushbutton momentary-contact switches. The switch  8  is used for switching the light on and off. The switch  9  is used for resetting the fan of the extractor hood or turning it off. The switches  10 ,  0 . 11  and  12  correspond to respective intensive stages of the fan or speed stages of the fan motor. The momentary-contact switches  9  to  12  are connected mechanically in such a way that, when a momentary-contact switch is pressed, they trigger one another and simultaneous pressing of the momentary-contact switches is mechanically prevented.  
         [0027]    The pushbutton momentary-contact switch  13  is used to activate an intensive stage. The intensive stage signifies briefly switching higher into the maximum rotational speed range. By the intensive stage, the conventional switch block  8  to  12  is expanded by one fully functional intensive stage, using a pushbutton momentary-contact switch  13  with a timing function.  
         [0028]    The intensive stage can be switched on in any operating state, i.e. at any speed of fan motor. It remains switched on in the predefined time period unless it is disconnected from the pushbutton momentary-contact switch by switching off (e.g. actuating switch  9 ) the fan motor. After the predefined time period has expired, the intensive stage deactivates itself. The device then carries on running in the originally set stage.  
         [0029]    For an additional intensive stage, the switch for the intensive stage must be mechanically decoupled from the other switches. The momentary-contact switch  13  for the intensive stage is also preferably equipped with its own time-delay switching element.  
         [0030]    When the intensive stage is activated, the stage that has been active until then is first switched off and only then is the intensive stage activated. As already mentioned, the intensive stage can be switched off manually at any time before the predefined time period has expired.  
         [0031]    When the intensive stage is switched off, irrespective of whether this is done automatically or manually, the previously set stage is automatically activated, as has also already been explained. The momentary-contact switch of this stage is still in the activated position so that the operator can recognize the stage used last.  
         [0032]    According to a further embodiment, instead of being equipped with an intensive stage, the extractor hood is equipped with a run-on or after run stage. The momentary contact switches  8  to  12  are assigned as in the first embodiment. However, the switch block is expanded by a fully functional run-on stage. In contrast to the first embodiment, the momentary-contact switch  13  for the run-on stage is mechanically connected to the other momentary-contact switches  9  to  12  by slides, ensuring that the momentary-contact switches trigger one another and lock one another to prevent them from being pressed at the same time.  
         [0033]    The run-on stage, like the intensive stage, can be switched on in any operating state. When the run-on stage is activated, any previously active stage is released. The run-on stage remains active for a predefined time period and then deactivates itself. In the process, the device switches off completely. The run-on stage can, like the other stages, be switched off by the switch-off or reset button  9 . However, it can also be switched off by switching on another stage.  
         [0034]    [0034]FIG. 3 shows a schematic view of a front operator control panel of a pushbutton momentary-contact switch block that constitutes a combination of the embodiments illustrated in conjunction with FIG. 2. In other words, the embodiment according to FIG. 3 contains an intensive stage and a run-on stage. For this purpose, the switch block in FIG. 2 is expanded by a pushbutton  14 . Here, the momentary-contact switch for the run-on function is also mechanically connected to the momentary-contact switches of the other stages, as was also the case in the previous embodiment. The intensive stage does not have any mechanical connection to the fan stages corresponding to momentary-contact switches  10  to  12 , but rather a mechanical connection to the run-on stage. This is intended to ensure that either the intensive stage or the run-on stage can be switched, but both cannot be switched simultaneously.  
         [0035]    [0035]FIGS. 4A to  4 D show perspective views of a rocker switch block according to the invention which contains four rockers  15 ,  16 ,  17  and  18  as operator control elements. In the case of an extractor hood, the rockers are assigned the following functions: the rocker switch  15  serves to switch the light of an extractor hood on and off. The blower of the extractor hood can be switched on to a stage “1” or can be switched off to a stage “0” using the rocker switch  16 . By the rocker switch  17 , the blower can be switched upward to a stage “2”. Finally, the rocker switch  18  is used to activate an intensive stage.  
         [0036]    [0036]FIG. 4A then shows a home position of the rocker switch block. All the rockers are located in the same position here. When the stage 1 is switched on according to FIG. 4B, the rocker  16  is activated and held mechanically in position. The blower of the extractor hood then runs to stage  1 .  
         [0037]    In FIG. 4C, the switching-on of the blower stage  2  is illustrated. For this purpose, the rocker  17  is activated and the rocker  16  for stage  1  remains in its switched-on position according to FIG. 4B if it was previously already switched on.  
         [0038]    The rockers  15  to  18  can be mechanically connected to a driver in a way that is appropriate functionally with respect to one another. As a result, it is possible to bring about a situation in which, when the stage  2  is switched on directly, i.e. the stage  1  has not yet been switched on, the rocker  16  for the stage  1  is also moved into the switched-on position by the driver.  
         [0039]    Finally, FIG. 4D shows the position of the rocker switches when the intensive stage is switched on. The rocker switch  18  for the intensive stage is, in contrast to the other switches  15  to  17 , controlled in a timed fashion. Therefore, after it has been activated, it is held magnetically in the contact position. After the end of the duration of the intensive stage, the rocker  18  is moved into its home position by a spring. The intensive stage thus switches off automatically. After the automatic switching-off of the intensive stage, the rocker switch position according to FIG. 4C comes about, and the device carries on running at fan stage  2 . As already explained in conjunction with stage  2 , the rocker  18  for the intensive stage can also be mechanically connected to the rockers  16  and  17 . As a result, the rockers  16  and  17  are moved automatically into the switched-on position according to FIG. 4D when the rocker  18  is activated.  
         [0040]    The intensive stage can be switched off at any time by activating the rocker  18 . The device then switches back to the maximum normal stage, i.e. in the present case stage 2. However, the intensive stage can also be switched off by the stage 0, i.e. the device, being switched off with the rocker  16 . A housing  19  of the rocker switch block contains a cuboid receptacle  20  beneath the rocker switch  18  for mounting a time-delay switching element. In principle, the time-delay switching element is configured according to FIG. 1.  
         [0041]    [0041]FIGS. 5A to  5 D show perspective views of a quintuple rocker switch block according to the invention. The rockers  15  to  18  have the same functions as those in the quadruple rocker switch block according to FIGS. 4A to  4 D. Moreover, a further timed rocker switch  21  for a run-on function is also present.  
         [0042]    The quintuple rocker switch block correspondingly has, in addition to the time-delay switching element  23  for the intensive stage, a further time-delay switching element  24  in an additional receptacle  22  for the run-on function (see FIG. 6B).  
         [0043]    In the home position according to FIG. 5A, the rocker  21  for the run-on function lifts off from the position of the other rockers  15  to  18 . This has proven advantageous for the operator control of an extractor hood. The rockers are mechanically connected to drivers with respect to one another in a way similar to the quadruple rocker switch block.  
         [0044]    The switching of the stage 1, stage 2 and the intensive stage is carried out, as illustrated in FIGS. 5B and 5C, in accordance with the rocker switch block as described in FIGS. 4B, 4C and  4 D. When the run-on function is activated, the rocker  21  is held magnetically in the contact position, as is also the case with the rocker  18  for the intensive stage. All the other rockers are moved into their zero position by a mechanical driver. This also applies to the rocker switch  18  of the intensive stage.  
         [0045]    After the end of the run-on function, the rocker  21  is moved into its home position by a spring. After the automatic switching-off, the switch position corresponds to that in FIG. 5A.  
         [0046]    [0046]FIGS. 6A and 6B show perspective views of the quintuple rocker switch block according to FIGS. 5A to  5 D from below. The cuboid receptacle  20  for the control element  23  is provided underneath the rocker  18  for the timed intensive stage, in the base of the quintuple rocker switch block. Likewise, the cuboid receptacle  22  for the further control element  24  for the run-on function is provided underneath the rocker  21 .  
         [0047]    As is shown by the exploded view in FIG. 6B, the control elements  23  and  24  are pushed into the receptacles  20  and  22 , and preferably clipped in there. The control element is pushed, by the magnet, forward through the base  19 . The rocker  21  is covered on the underside with an iron-containing material that adheres to the magnet.  
         [0048]    In summary, it is to be noted that, in this way, an electromechanical switch is implemented which in its operator control characteristic is based on the electronic control systems that have been used previously, but is significantly more cost-effective. This is possible by virtue of the fact that robust parts that are manufactured by series production are combined with modified and newly-developed components to form a pushbutton momentary-contact switch or a switch block with a timer function. With this novel switch it is also possible to implement device block switches with a plurality of switches. The field of use of the switch or block switch is not restricted to the field of extractor hoods but rather can also be extended to any domestic appliances, air-conditioning units, ventilation units, miniature devices, etc.