The invention relates to a data transmission device com¬ prising a unit formed of a identification card and its holder enclosure wherein the stored data is read by a distant reading device.

At present more and more data transmission devices are being introduced which are small sized devices comprising active and passive data , for examples so called smart cards where a micro chip has been disclosed in a card like a credit card or bank card. The data in the micro chip has to be unloaded and correspondingly the additional data or changed data has to be fed to the card with a suitable reading device. In the latest type of cards the reading is conducted by passing the card at a distance from the reading device. This kind of application is simple and fast because the card does not have to be inserted in any into the reading device itself but it is sufficient that the user for example passes the reading device whereby the reading device reads the data in the micro chip and changes it simultaneously. This kind of applications are being tested as means of payment in collective transportation systems. The card can of course also be applied to many other purposes, for example as an identification card at an employee to control working hours simultaneously func¬ tioning as an identification card. At the same time the card can be provided with a person's photograph whereby by the assistance of the computer connected to the control system the corresponding photo appears in the monitor. Thus the personal data and the appearance can be compared to the data on the card.

To equip a thin card with the necessary source of informa- tion as well as transmission and receiving means may be difficult . Further the used card cannot be reused if the appearing data is changing, for example if the employee is

quitting the job the card is useless even if the data can be reprogrammed but the data printed on the card remains the same.

The aim of the present invention is to create a more advan¬ tageous data transmission device which can be used again and again simply by reprogramming the chip in the card. This is achieved according to the invention with an identi¬ fication card which as known per see is provided with the desired identification data whereas the holder card to which the identification card is attached is provided with the transmission/receiving means and storing means for the data intended for cooperation with the corresponding means of the reading device. the manufacture of such a holding card is simple. The holder is usually made of a casinglike part with a closed bottom. In this bottom a recess is made encircling said bottom, in which recess the induction coil functioning as a transmitter and a receiver is arranged, said coil also being connected to the micro chip embedded in the bottom. These transmission and receiving means as well as the recording means are known per see and described for example in US patent 4 572 776 and PCT application WO 85/03831. It is clear that the means may have other practical solutions, essential is, that the invention consists of a unit comprising a conventional card and a holder thereof provided with receiving and transmission means known per see.

The holder may be like a casing, the bottom of which is equipped with the data transmission and recording means and covered by a protective coating. Over this coating the card is pushed in usual manner into position and the casing can by suitable clamp or fastening means, e.g. a needle or alike, be fastened on the garment or the casing can hang around the neck with a suitable chain. In this connection the term "casing" means all kinds of holding or supporting means for conventional plastic cards.

The invention is explained more in detail by reference to the enclosed drawing, wherein

Figure 1 shows a holder according to the invention in a longitudinal cross section,

Figure 2 shows the casing according to figure 1 from above, and

Figure 3 shows the casing according to figure 1 in per¬ spective, the card partly inserted in position.

The invention according to figures 1 - 3 is thus formed of a casinglike holder 1, being a rectangular casing with relatively low edges. The upper portion of the edges along the longitudinal edges of the card inwardly projecting flanges 2 are provided for holding the card pushed into the casing. At the bottom of the casing near the four corners thereof are apertures 3 intended for the fastening means of the casing, in the application according to figure 3 the ends of the chain 6 have been fastened into the apertures.

The bottom of the casing is provided with an oval recess wherein the induction coil 4 is arranged. The coil is connected to a micro chip 5, which also is embedded in the bottom of the casing. The coil 4 and the micro chip 5 is covered with a protective coating. Thus the means are not damaged when the card is pushed into position in the casing.

In the method of the invention it is still possible to use thin conventional so called plastic cards provided with conventional data. It is more convenient to provide the casing 1 with means required for data transmission, i.e. the induction coil 4 and the micro chip 5. The plastic card used in this assembly can easily edited or changed,

whereby the casing can be reused by reprogramming it and by entering new or changed data.

The use of the card entity is easy as it is intended to be used together with a reading device, where the reading occurs from a distance. The card and casing are passed before the reading device, whereby the data is transferred to the reading device for further prosecution.