Abstract:
The present invention relates to a compact drive system serving to deflect a push force to move a carriage assigned to the chip card and mounted in a chip card receiving unit. A flexible, pressure-transmitting force conductor is provided in the form of individual spheres, the force conductor being assigned a direction-deflecting guide and a push rod provided with an actuating member. The force conductor is driven by a control slide engaging in the duct, the control slide being connected by a gear to a positioning motor.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
   The present invention is a continuation of international application PCT/DE02/03854, filed Oct. 11, 2002, which designated the United States, and further claims priority to German application 10160276.6, filed Dec. 7, 2001, the both of which are herein incorporated by reference. 

   BACKGROUND OF THE INVENTION 
   The present invention relates to a drive arrangement for at least one smart card holder, the holder being arranged in a tachograph. The drive arrangement is arranged so as to move a smart card to the removal position, and includes: a reversible actuating motor, a control slide which is operatively connected by a transmission to the actuating motor, and transmission means which are provided between the control slide and the smart card holder. 
   Tachographs of this generic type are generally designed as built-in units with a flat, cuboid built-in housing. There is therefore very little physical space available from the start for a smart card holder and its drive means. This results in a smart card which is located in the read/write position being moved to the removal position. On the other hand, smart cards which have been deformed during their use, for example by being curved or rippled, particularly when they have been inserted into the read/write position exclusively by hand, with the necessary amount of force being applied, result in a considerable amount of force being required in order to allow them to be transported to the removal position again. This force requirement must be applied and transmitted by the drive means, thus necessitating a robust design and hence sufficient physical space. Furthermore, on the one hand owing to the small physical height required by the tachograph and on the other hand owing to the need to make contact, it is also expedient to associate the smart card holder and the drive means directly with the printed circuit board of the tachograph. However, even though it is designed to largely fill the format of the outline of the tachograph housing, there is a considerable lack of space available on the printed circuit board owing to the high component density, so that an arrangement of the smart card holder and of its drive means that is still possible generally necessitates a change in the direction of the thrust force which is exerted by the control slide. This is particularly true in the case of a tachograph which is equipped for simultaneous recording of at least the work and rest times of the driver and co-driver, and in which two smart card holders are provided and in the end, furthermore, only a single actuating motor must be provided, for cost reasons, by means of which the smart card for the driver or that for the co-driver must be transported to the respective removal position with the interposition of transmission means which change the direction of the force flow. 
   A drive arrangement which is known in this context from German Utility Model 200 15 100.2 envisages belt-driven means between a control slide, which is driven by an actuating motor, and the carriages which are mounted in the relevant smart card holders and are associated with the smart cards, in order to change the direction of the movement of the control slide to the direction for emitting the smart cards. Owing to the high friction losses resulting from transverse forces and the system-dependent force distribution, such transmission means necessitate an increase in the power of the actuating motor and, owing to the necessary guidance accuracy of the components on which the belt-drive elements are formed, result in a very high degree of manufacturing effort, and occupy considerable physical space. 
   SUMMARY OF THE INVENTION 
   The object of the present invention is thus to provide a drive arrangement of this generic type which offers optimum use of the available power from the actuating motor with a high degree of functional reliability using components which can be produced and installed in a mass production environment, and which can be implemented with as little space requirement as possible. 
   The stated object is achieved in that a flexible, force-transmitting force conductor is used as the transmission means, and in that the force conductor has an associated direction-changing guide. 
   One preferred exemplary embodiment is characterized in that individual pressure elements which are guided in a channel such that they can move freely are provided as force conductors, and in that balls are provided as pressure elements. 
   One advantageous exemplary embodiment consists in that the force conductor and the control slide are in the form of a single component which can be produced by injection molding, in which case the force conductor comprises a strand, which is produced from elastomer material and has sliding bodies which are integrally formed on it and are composed of non-elastomer material. 
   Further embodiment variants and expedient refinements of the invention are described in the dependent claims that are not cited, or will become evident from the description of the drawings. 
   The major advantage offered by the invention is that a modular drive arrangement can be formed, which comprises the control slide, the step-down transmission which drives the control slide, and the transmission means, for which modular drive arrangement the preferred exemplary embodiment provides a housing which can be closed by a cover. This assembly in which only the actuating motor which is arranged on the opposite side of the printed circuit board of the tachograph engages by means of a pinion that is mounted on the motor shaft, occupies little space and can be varied in a simple manner. One major factor is that the drive arrangement can be produced by technically simple, robust means which can be installed easily, and offers satisfactory functional reliability with a high efficiency. The solution that has been found is also insensitive to tolerances and, owing to the largely direct action of the control slide on the smart card holder and on a carriage which is associated with the smart cards and is mounted in the smart card holder so that it can move, requires only a short operating time for moving a smart card from the read/write position to the removal position even when using a relatively low power actuating motor. 
   It is also worth mentioning that the control slide need not necessarily be guided at right angles to the movement directions of a smart card. The direction of the force flow can be changed as required via the flexible force conductors that are provided. Furthermore, when using two smart card holders which are arranged alongside one another, it is also irrelevant whether they are arranged close to one another or relatively far apart from one another. In any case, the solution according to the invention can also be used when the smart card holders are arranged at the greatest possible distance apart form one another in the relevant tachograph. Furthermore, when individual elements which are not connected to one another, for example balls, are used as a force conductor, an asymmetric arrangement of the control slide with respect to the smart card holders is possible without any additional component complexity. The push rods which are advantageously held in the guides associated with the force conductors at the same time represent locking elements, which can be held in a sprung manner against the housing of the drive arrangement. The push rods and the operating elements which are integrally formed on the push rods also have an adapter function, that is to say they may be designed for operation of smart card holders of different configuration. However, it is also feasible to dispense with the push rods and to form projections, which engage in the guides for the force conductors, on the carriages which are associated with the smart cards. 
   For the sake of completeness, it should also be mentioned that the chosen transmission principle can operate in three dimensions, so that the control slide may also be arranged away from the movement plane of the smart cards. It should also be mentioned that, apart from individual, preferably commercially available, steel balls, ball chains, chains composed of spherical or barrel-shaped chain links which can be coupled to one another or flexible strands which are produced integrally and have spherical sections may also be used as the force conductors. In the same way, force conductors composed of spring steel, are guided in the housing of the drive arrangement and are in the form of strips or wires may likewise be provided in some suitable manner. It is also possible to use as force conductors T-shaped pressure elements which are guided in a groove that is formed in the housing and are held in the grove by means of the cover and which are connected to one another in a flexible manner, for example by means of integrally formed loops. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     The invention will be explained in the following text with reference to drawings, in which: 
       FIG. 1  shows a view from underneath of the drive arrangement according to the invention, illustrated partially schematically, with a partial illustration of the removed cover and an illustration of the association between the drive arrangement and the smart card holders in a tachograph, 
       FIG. 2  shows a front view of the tachograph, which serves for orientation purposes, with smart card holders which are arranged alongside one another on one plane, 
       FIG. 3  shows a plan view of a component which comprises two force conductors and a control slide, 
       FIG. 4  shows a section through the drive arrangement along the section line A in  FIG. 1 , 
       FIG. 5  shows a partial section through the tachograph with a side view of the drive arrangement installed in the tachograph, as well as a partial section along the section line B in FIG.  1 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As can be seen from  FIG. 1 , the functional elements of the drive arrangement are essentially mounted in a housing  1  which can be closed by means of a cover  2 .  3  denotes a drive pinion, which is mounted on the motor shaft  4  of an actuating motor  5  ( FIG. 5 ) which engages in the housing  1 . A schematically illustrated step-down transmission  6 , downstream from the drive pinion  3 , is operatively connected to a pair of gearwheels  7 ,  8 , which are mounted on a hollow shaft  9 . The gearwheel  8  engages with a toothed system  11  which is formed on a control slide  10 . The control slide  10  is mounted in the housing  1  such that it can move, and has a finger  12  which engages in a channel  13 , which is intended for bearing two or more freely moving balls which are used as flexible, pressure-transmitting force conductors  14  and  15  and are respectively annotated  16  and  17 . This solution allows large actuating forces to be transmitted with relatively little friction. In addition to the pair of gearwheels  7 ,  8 , the control slide  10  is also guided by a guide tongue  19  ( FIG. 4 ) which engages in a slot  18  that is formed in the housing  1 . End stops, which are formed in the housing  1  and are associated with the control slide  10 , are annotated  20  and  21 . Hollow pins  22 ,  23 ,  24  and  25 , which are provided with holes through them that are not annotated any further are used to hold the cover  2  in that spacer bolts which are integrally formed on the cover  2  and that two of which  26  and  27 , are shown in  FIG. 1  engage in recesses, which are not annotated, in the hollow pins  22 ,  23 ,  24 ,  25 . The push rods which are guided in the channel  13  are annotated  28  and  29 , and their operating elements  30  and  31  are designed in a suitable manner for interaction with smart card holders  32  and  33 , which are indicated in  FIG. 1 , for the relevant tachograph. 
   In the functional state illustrated in  FIG. 1 , the drive arrangement is in a neutral position from which either one or the other smart card  34  or  35  can be moved to its removal position. For this purpose, the operating elements  30  and  31  of the push rods  28 ,  29  interact with carriages  36  and  37  with which the smart cards  34 ,  35  are fitted, and with tongues  38  and  39  which are formed on the carriages  36 ,  37 . The carriages  36 ,  37  are mounted in suitable manner such that they can move on mounts  40  and  41  of the smart card holders  32 ,  33 . If necessary, the carriages  36 ,  37  have associated locking means. 
     FIG. 2  is intended to explain how the smart card holders  32 ,  33  are arranged in a tachograph which, for example, has a cuboid housing.  FIG. 2  shows a front panel  42  which covers the built-in housing part of the tachograph. A window cutout is annotated  43 , through which the indication of a display  44  is legible. In addition, a number of keys  45 ,  46 ,  47  and  48  are passed out of the front panel  42 . In this case, the keys  45  and  48  are used for registration by the driver and co-driver, the keys  6  and  7  are used in connection with the keys  45  and  48  in order, inter alia, to release the respective personal smart cards  34 ,  35  associated with the driver and co-driver. A plug socket, which is used for diagnosis purposes, is closed by a cover  49 . Guide slots  50  and  51  which are fitted in the front panel  42  and some of which are recessed in the form of funnels are used for initial orientation during insertion of the smart cards  34 ,  35  by the driver and co-driver into the respective smart card holders  32 ,  33  (which are located in the built-in housing part) of the tachograph. Cutouts  52  and  53  in the projection  54  (which is in the form of a bead) on the front panel  42  are used as input troughs for initial insertion of the smart cards  34 ,  35  into the respective read/write positions. A slot which is annotated  55  is provided for the print medium of a receipt printer that is arranged in the tachograph to pass through. A key  56  is used to start printing. A lead seal is annotated  57 , securing a screw connection between the front panel  42  and the built-in housing part.  FIG. 2  also shows bolt elements  58 ,  59  and  60 ,  61  which are pivoted in front of the smart cards  34 ,  35  and are mounted in the smart card holders  32 ,  33 . 
     FIG. 3  shows a solution which is optimized for mass production, in which force conductors  62  and  63  which are associated with the smart card holders  32 ,  33 , and a control slide  64 , form a single component which can be formed by injection molding. In this case, each force conductor  62 ,  63  comprises a respective strand  65 ,  66 , which is manufactured from elastomer material, and barrel-shaped sliding bodies, which are integrally formed on them by means of the two-component injecting-molding technique and are composed of non-elastomer material. The sliding bodies which are integrally formed at a specific distance “a” from one another on the strands  65 ,  66  are respectively annotated  67  and  68 . As  FIG. 3  also shows, the force conductors  62 ,  63  are connected via the strands  65 ,  66  directly to the finger  69  (which engages in the channel  13 ) of the control slide  64 , which is expediently formed from the same material as the slide bodies  67 ,  68 . A cutout (which is annotated  70 ) is used to avoid accumulation of material on the finger  69 . Otherwise, the control slide  64  is in the same form as the control slide  10 , that is to say it is provided with a toothed system  71  and with a guide tongue  72 . At this point, it should also be mentioned that, for molding reasons, the sliding bodies  67 ,  68  are axially slotted in order to form the force conductors  62 ,  63 , and the cross-sections of the connecting strands  65 ,  66  can be designed to correspond to the profile of the slots. 
   The section shown in  FIG. 4  illustrates in particular how the housing  1  and the cover  2  are joined together once the functional parts of the drive arrangement have been inserted into the housing  1 . A centering pin  73 , which is formed on the cover  2  and engages in the hollow shaft  9 , as well as an anti-rotation device, which is not illustrated but is expediently provided in the area of the bushing for the motor shaft  4 , are used to align the cover  2  on the housing  1 . A groove which is formed on the cover  2  and is supplementary to the channel  13  is annotated  74 . The cover  2  is attached to the housing  1  by mounting the drive arrangement on the already mentioned printed circuit board  75  in the tachograph. This is done by means of a number of screw connections, of which three screws  76 ,  77  and  78  can be seen in FIG.  5 . Threaded holes, which are not shown in detail, are associated with the screws  76 ,  77 ,  78  in the spacer bolts  26 ,  27  and in the pin  73 , and these screws engage in the hollow pins  22 ,  23 ,  24 ,  25  and in the hollow shaft  9 . This means that the housing  1  is attached indirectly to the printed circuit board  75  via the cover  2 . Supports  79 ,  80  and  81  which are provided with through-holes, are formed on the housing  1  and have attachments  82 ,  83  and  84  (which are integrally formed on them and are used for alignment of the drive arrangement on the printed circuit board  75 ) are used as a rest. One of two forked light barriers which are fitted to the printed circuit board  75  is annotated  85 , and these are used in conjunction with the guide tongue  19  on the control slide  10  for controlling the actuating motor  5 . This means that, depending on the selected rotation direction of the actuating motor  5 , either the push rod  28  or the push rod  29  is operated in the direction of emitting a smart card  34 ,  35 , starting from the neutral position as illustrated in  FIG. 1 , by means of the control slide  10  and the force conductors  14 ,  15 , and the control slide  10  is then moved back to the neutral position in order to ensure that another smart card can be inserted. In this context, it should be mentioned that pin/slot connections are provided between each of the push rods  28 ,  29  and the housing  1 , are used as anti-rotation devices and allow the drive arrangement to be handled without any problems before it is installed in a tachograph. 
     FIG. 5 , which shows sections of a side wall  86 , of the base  87  and of the rear wall  88  of the built-in housing part  89  of the tachograph, illustrates the small amount of space required for the drive arrangement according to the invention, particularly with regard to the physical height and physical depth.  FIG. 5  also shows the association between the smart card holders  32 ,  33  and the printed circuit board  75 , in the partial section B. Spacing bolts  90 , which are in the form of spacers from the base  87 , are provided with threaded holes and are integrally formed on the mounts  40 ,  41 , and screws  91  are used for this purpose. A driver which is integrally formed on the carriage  36 ,  37  and is associated with the smart cards  34 ,  35  is annotated  92 . A cutout which is provided in the mounts  40 ,  41  is annotated  93 , and forms the free space for the movement of the tongues  38 ,  39 , which are formed at an angle on the carriages  36 ,  37  and for the entry of the operating elements  30 ,  31 .