Abstract:
The aim of the invention is to prevent the plate contacts of chip cards from wearing as a result of vibrations that occur during the operation of a vehicle. To achieve this, the spring contacts of the read/write set of contacts in a holding device for chipcards are separated from the plate contacts of a chip card that has been inserted into the holding device, for a period, during which no trip or driver-related data is transmitted and said contacts are closed for only a relatively short time, i.e. during the reading of the chip card data into the relevant data recording device and during the writing of recorded data to the chip card. The holding device is configured in such a way that the relevant chip card remains inaccessible when the contacts are separated.

Description:
BACKGROUND OF THE INVENTION 
   The invention relates to a holding device for chip cards which are used in vehicles, have the purpose of person-related collection of travel data and which have a card holder which guides the chip cards between a removal position and a read/write position, and have output means, the output means bringing about, after the actuation of a request element, transfer of a chip card in the read/write position into the removal position. 
   The collection, in particular, of working times and times of rest of the drivers of utility vehicles requires, because of the documentary value of this data, reliable protections for avoiding disruptions which are carried out with fraudulent intent, for example by briefly pulling on a chip card during the transmission of data between the data collection device and the chip card or by virtue of the fact that films or electrically conductive material are pushed forward into the holding device of the chip cards. On the other hand, there is the risk of functional faults owing to the considerable climatic fluctuations which occur in the environment in which a utility vehicle is used, and consequently temperature-related and moisture-related changes in the material and also the oscillation level and travel-related vibrations which occur while the utility vehicle is operating. 
   These mechanical oscillations can lead, for example, to rapid wear of contacts, that is to say to complete wearing through of the relatively thin surface contacts of the chip cards which are embodied as small gold plates if there are relative movements between a chip card which is in the read/write position and the set of read/write contacts which is assigned to the chip card. 
   Owing to the vehicle-related application, in terms of the manufacture and mounting of a holding device for the chip cards it is basically to be assumed that tolerances which are appropriate for large scale manufacture are provided, and depending on the tolerance situation a more or less large sensitivity to oscillation occurs between a chip card and the read/write contacts which are positioned on it. Considerable additional tolerances have to be taken into account in particular if the holding device for the chip cards is not manufactured as an autonomous assembly which is functionally complete but rather the card holder and the set of read/write contacts are mounted separately from one another, for example on a printed circuit board of a tachograph which is used as a data collection device. In addition, the levelness of printed circuit boards is subject to tolerances and to climate-related fluctuations, and the chip cards have relatively large differences in thickness and can be bent. 
   SUMMARY OF THE INVENTION 
   An object of the present invention has thus been to provide a holding device in which, despite the compatibility with large scale manufacture and the robustness which are necessary for use in a utility vehicle as well as the necessary protection against tampering, oscillation-related and vibration-related wear of the plate contacts of the chip cards is largely reduced. 
   The means of achieving the object which is set are characterized in that the holding device is assigned an apparatus which, after a chip card has been input into the read/write position and after data has been read out from the input chip card, disconnects the spring contacts of a set of read/write contacts from the plate contacts of the chip card, closes the spring contacts of the set of read/write contacts after the request element has been actuated, and the plate contacts of the chip card which has been input, and triggers a release of the output means after travel data which has been collected in the meantime in a memory which is independent of the chip card has been written into the chip card. 
   One preferred exemplary embodiment provides that the inputting and outputting of chip cards take place automatically, a conveying means which is actuated by motor engaging in the movement space of the chip card, that the transfer path of the chip card within the holding device is longer than the length of a chip card, and that, apart from a switch which signals a pushing forward and removal as well as the reaching of the read/write position of a chip card there is provided at least one further switch which, when a chip card is displaced in the output direction, signals disconnection of the plate contacts of the chip card from the spring contacts of the set of read/write contacts when the removal position has not yet been reached. 
   A specific exemplary embodiment which is suitable for a holding device which has a smaller transfer path in comparison with the preferred exemplary embodiment is characterized by the fact that the card holder and the set of read/write contacts are attached to one and the same carrier, and that the spring contacts of the set of read/write contacts can be raised or lowered at right angles to a chip card in the read/write position by means of an auxiliary force, in particular that an actuation element which connects the free ends of the spring contacts of the set of read/write contacts is provided, and that an electromagnet which is attached to a printed circuit board is assigned to the set of read/write contacts in such a way that the armature of the electromagnet is operatively connected to the actuation element. 
   The novelty whose implementation includes a method in which the data of a chip card, when the latter is pushed forward into the holding device, or read into a data memory of the data collection device and data which has been collected in the meantime is transmitted, before it is output, into the data memory of the chip card, or the data of the chip card is updated, at regular intervals, at the latest however when the chip card is to be output, makes it possible for the contacts of the chip card and set of read/write contacts to be closed only if data is transmitted. This means that in the rest of the time when a chip card is in the holding device the contacts are separated and thus oscillation-related wear of the plate contacts of the chip cards is not possible. At the same time, the invention ensures that a chip card and/or the holding device are protected against tampering even when the contacts are disconnected. 
   The preferred exemplary embodiment provides the smallest degree of expenditure in order to avoid oscillation-related wear of contacts. In this exemplary embodiment, only a second photoelectric barrier which signals the parked position of the chip card is necessary on condition that there is a sufficient conveying path, longer than the length of a chip card, available in the conveying direction of the chip cards in the holding device. 
   Another design of the holding device, in which a sufficient conveying path for disengaging the contacts when a chip card is inaccessible is not provided, makes it necessary to carry out a relative movement between the set of read/write contacts or merely its spring contacts and the card holder. Preferably, in this case, the set of read/write contacts is attached directly to a carrier, for example a printed circuit board, on which the card holder is also arranged. In the respective specific exemplary embodiment, the free ends of the spring contacts of the set of read/write contacts are secured in an actuation element which is operatively connected to the armature of an electromagnet. The latter can also be mounted directly on the printed circuit board and placed in contact with corresponding conductor tracks, specifically on the opposite side from the set of read/write contacts. The electromagnet is preferably configured in such a way that when current is supplied to the coil winding, the armature of the electromagnet acts on the actuation element, and the contacts of the chip card and set of read/write contacts are thus closed, that is to say the actuation element and the armature can be arranged as components which are independent of one another in the respective structural unit. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     The invention will be explained in more detail below with reference to drawings, in which: 
       FIG. 1  shows a front view of a tachograph, 
       FIG. 2  shows a holding device, embodied as an autonomous assembly, in a perspective view, 
       FIG. 3  shows a section along the sectional line A in  FIG. 2 , a chip card which is input into the holding device being located in the read/write position, 
       FIG. 4  shows a view according to  FIG. 3  in which the chip card is located in a parked position in which the contacts of the chip card and set of read/write contacts are separated, the holding device being however closed off in an inaccessible fashion, 
       FIG. 5  shows a largely schematic sectional view of an arrangement for closing the contacts for a chip card and a set of read/write contacts for a holding device in which a conveying movement of a chip card is not possible in the locked state. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In  FIG. 1 , a shutter or a front panel of the respective tachograph  2  is designated by  1 , said shutter or front panel terminating at the front a housing with a rectangular cross section (not shown in  FIG. 1 ) which extends at right angles to the plane of the page. A display device  3  and keys  4 ,  5  and  6 ,  7  are guided in the front panel  1  in a secured fashion, the keys  4 (I) and  7 (II) are used to register the driver and front seat passenger, the keys  5  and  6  are used to request the chip cards assigned to the respective driver and front seat passenger.  8  designates a window cut out which is formed in the front panel  1  for observation purposes. A cover  9  which is mounted in a sprung fashion covers a plug socket;  10  represents a warning lamp. Slots  11  and  12  are used to input the chip cards of the driver and front seat passenger into suitable holding devices of the tachograph  2 , one of which is illustrated as  FIG. 2  and designated by  13 . The slots  11 ,  12  are, as is shown also by  FIG. 1 , basically formed from respectively funnel-shaped depressions  14  and  15 . In addition, a cutout  16 , which is covered by a front element  17  of a printing device  18  is provided in the front panel  1 , said coverage being such that the front element  17  is pushed forward into the front face of the front panel  1  of the tachograph  2  in a structural fashion, in particular flush with the surface. 
   For the sake of completeness it should be noted that the printing device  18  comprises a carriage by means of which it can be moved out of the tachograph  2 . A bistable latching gear, which can be unlocked and locked by actuating the front element  17 , which thus serves as a key, can be assigned to the carriage. In addition, a plurality of keys  20 ,  21  and  22 ,  23  and  24  are mounted in the front element  17  which is provided with a gripping bar  19 . Said keys serve, together with the keys  4  and  7 , for the selection of the most important working time data by the driver and front seat passenger, for leafing forward and backward in the respective data records of a selected type of data and for triggering printing.  25  designates an outlet opening for the printed recording material. 
   The holding device  13  which is illustrated in  FIG. 2  has a plate-shaped card holder  17  on which spacing bolts  27 ,  28  and  29 , provided with threaded bores which are not designated in more detail, are formed for connecting the holding device  13  by means of flanges at the installation location, in this case to a printed circuit board of the tachograph  2 .  30  designates a drive motor which is preferably a DC motor which engages with an obliquely toothed cylindrical gear  32  via a worm  31  which is arranged on the shaft of said DC motor. Said cylindrical gear  32  is attached to a connecting shaft  33  which is mounted on the card holder  26  and intermeshes via a worm  34  with a gearwheel  35  which is also embodied as an obliquely toothed cylindrical gear and is connected fixed in terms of rotation to a conveying shaft  39  which bears a plurality of friction elements  36 ,  37  and  38 . Supporting pillars and bearing arms which are formed on the card holder  26  and assigned to the connecting shaft  33  are designated by  40 ,  41 ,  42  and  43 . The conveying shaft  39  is mounted in bearing limbs  44  and  45  which are also formed on the card holder  26 . On the other side, the conveying shaft  39  of a rocker  46  serves as a bearing axle. The rocker  46 , which is embodied as a plate-shaped body which is provided with side elements  47  and  48 , has breakthroughs  49 ,  50  and  51  for reaching the friction elements  36 ,  37 ,  38  in the movement space of the chip cards and is provided on the one hand with a closing element  52  which is directly formed on, as well as with key elements  53  and  54 . The latter are recesses  55  which are formed in the cardholder  26 ; the closing element  52  interacts with a groove  56  which corresponds to the closing element  52 .  57  designates a mount which is recessed into the card holder  26  and has the purpose of guiding the chip cards. As is also apparent from  FIG. 2 , a cutout  58 , into which a set  59  of read/write contacts can be pushed forward from the side of the rocker  46  which is assigned to the data cards is also provided in the rocker  46 . Here, pin connections  61  and  62  which are formed between a frame  60  of the set  59  of read/write contacts and the rocker  46  have the purpose of orienting the set  59  of read/write contacts and locking latches  63 ,  64 ,  65  and  66  which are formed on the frame  60  have the purpose of locking the set  59  of read/write contacts on the rocker  46 . A section, connected to the set  59  of read/write contacts, of a flexible conductor track  67  is designated by  68 ; a centering pin  69  serves to orient the section  68  of the conductor track before it is soldered to the individual spring contacts, embodied as leaf springs, of the set  59  of read/write contacts, two of which are illustrated in  FIGS. 3 and 4  and designated by  70  and  71 . A further section  72  of the conductor track is used to electrically connect the drive motor  30 .  73  designates a conductor track belt, with which reflective light barriers  74  and  75  are placed in contact. The conductor track belt  73  is, as is shown by  FIGS. 3 and 4 , attached to the underside of the card holder  26 ; suitable breakthroughs (not designated in more detail) in the card holder  26  are assigned to the reflective light barriers  74 ,  75 . For the sake of completeness, it is also to be noted that, for example, leaf springs are not absolutely necessary but expediently assigned to the rocker  46 , said leaf springs being attached to the card holder  26  and acting on the rocker  46  in such a way that even when a card holder  26  does not have a chip card pushed forward into it, the closing element  52  is always in engagement with the groove  56 , and in this way exerts a sealing function. If, in this state of the holding device, a chip card  76  is pushed forward into the tachograph  2  through one of the pre-orienting slots  11  or  12  in the front panel  1  and has been introduced manually as far as the friction elements  36 ,  37 ,  38  of the conveying shaft  39 , the rocker  46  is lifted up, owing to the wedge mechanism effect between the closing element  52  and the chip card  76  and pivoted about the conveying shaft  39  and triggers a switching function of the reflective light barrier  74  which actuates the drive motor  30 . As a result, the conveying shaft  39  is driven, and the chip card  76  is transferred further, specifically automatically, as far as the delimitation of the mount  57  and until the drive motor  30  is switched off by a switch  77  which signals when the read/write position of a chip card  76  is reached, and is preferably structurally arranged in the frame  60  of the set of read/write contacts. While the chip card  76  is being transferred into the read/write position, the rocker  46  has been pivoted back into the closed position either owing to the aforementioned leaf springs (however not illustrated) or else in conjunction with the key elements  53 ,  54 , and, as is apparent from the sectional view in  FIG. 3 , has been automatically locked in this position owing to the small degree of play between the chip card  76  and the key elements  53 ,  54 . After the chip card  76  has been positioned in the write/read position, a testing procedure is carried out and the data which is stored in the chip card  76  is read out. 
   According to the invention, the chip card  76  is then displaced, that is to say the drive motor  30  and thus the conveying shaft  39  are actuated as a function of a program so as to output the chip card  76 . The conveying of the chip card  76  in the output direction is stopped as soon as a change in state of the reflective light barrier  75  occurs. In the parked position which is then reached, the contacts of the set  59  of read/write contacts are disconnected, as is shown by  FIG. 4 , from the contacts of the chip card  76 , but the rocker  46  remains locked. At the latest when one of the keys  5  or  6  is actuated and the chip card  76  is to be output, the chip card  76  is firstly transferred back into the read/write position and the data of the chip card  76  is updated in accordance with the travel-dependent data and events which have been collected in the meantime in the memory of the tachograph  2  inside the device. Then, also under program control, the chip card  76  is transferred into the removal position, where it can be removed manually, and in this process a signal of the reflective light barrier  74  deactivates the drive motor  30 . If the chip card  76  is not removed immediately, the drive motor  30  is stopped under time control. 
   For the sake of completeness it will also be noted that when the chip card  76  is output, the reflective light barrier  75  is without effect and the rocker  46  is caused to pivot automatically as a result of the interaction of the wedge-shaped closing element  56  with the chip card  76 . In addition, it is to be noted that it is expedient to update the data of a chip card  76  in the holding device  13  relatively often, for example when a defined quantity of data is reached, so that a chip card can be output in a relatively short time. Shock-related displacements of the chip card  76  are therefore not critical insofar as a program is used to check whether there is still in general a chip card  76  in the holding device  13 , and if this is the case, the data-reading and conveying routine according to the invention is repeated several times within the holding device  13  between the read/write station and the parked position, if necessary. 
   In other embodiments of the holding device, which only permit the chip cards to be pushed forward manually, or allow the chip cards to be pulled in automatically over a distance which is not conceivable for the contacts of a chip card and of the set of read/write contacts to be moved apart as a result of the displacement of the chip card, it is conceivable to construct the set of read/write contacts as a carriage or to arrange said set of contacts on a carriage which is mounted on a carrier, in a displaceable fashion, not necessarily displaceable in the direction of movement of the chip cards, which may be the printed circuit board of a device, for example of a tachograph. However, one expedient variant can also consist in that, in the fact that the set of read/write contacts is fixedly arranged, and the card holder is pivotally mounted, the card holder being capable of being engaged with an eccentric shaft which can be activated by motor. 
     FIG. 5  proposes an exemplary embodiment which, for the purpose of separating the contacts of the chip card and set of read/write contacts, provides for the spring contacts of the set of read/write contacts and the plate contacts of a chip card to be closed and respectively separated under electromagnetic control, specifically at right angles to the plane of movement of the chip card. For this purpose, the free ends of the spring contacts (two of at least six are illustrated in  FIG. 5  and designated by  79  and  80 ) which are embedded or mounted in a set  78  of read/write contacts are secured in an actuation element  81 .  82  designates a carrier, for example a printed circuit board, to which the set  78  of read/write contacts is attached in that the ends  84 ,  85 , mounted in a frame  83  of the set  78  of read/write contacts, of the spring contacts  79 ,  80  are soldered to conductor tracks of the printed circuit board  82 . An electromagnet  86  whose armature  87 , which is of stepped construction for the necessary limitation of the travel, engages on the actuation element  81  through an opening  88  in the printed circuit board  82  is arranged on the opposite side of the printed circuit board  82 . The electromagnet  86  is composed, as is also apparent from  FIG. 5 , of a pot-shaped housing  89  which can be closed off by a cover plate  90 , a two-component return ring  91  pushed forward into the housing  89 , and a coil body  93  which bears the winding  92 . The connecting lines  94  of the (not illustrated in  FIG. 5 ) in the return ring  91  and in winding  92 , which are guided through suitable openings the housing  89  are closed off in the exemplary embodiment according to  FIG. 5  by means of a plug  95 . However, it is also conceivable to construct the electromagnet  86  in such a way that it can be provided with connecting lugs and equipped and soldered with SMDs.  96  designates a chip card which is located in the read/write position. 
   In the functional state illustrated in  FIG. 5 , the winding  92  of the electromagnet  86  is not supplied with current so that the armature  87  is lifted off from its stop, the bottom  97  of the housing  89  by the spring contacts  79 ,  80 , preferably embodied as leaf springs, of the set  78  of read/write contacts. If the winding  92  is supplied with current, the armature  87 , which strikes against the bottom  97  of the housing  89 , acts on the actuation element  81  and moves the spring contacts  79  or  80  into a sprung operative connection with the plate contacts of the chip card  96 . This solution has the advantage of low power consumption. On the other hand, it would also permit the likewise conceivable reverse function, that is the quiescent current mode which requires a fixed connection between the armature  87  and actuation element  81 , by virtue of the fact that owing to the effect of a buffer battery which is internal to the device, travel data which has been generated can be written into the chip card memory even when the vehicle battery fails.