CONNECTOR FOR A CARD READER ABLE TO ACCEPT DIFFERENT CARD THICKNESSES

Abstract: The connector for a microcircuit-card or smart-card reader comprises a frame (1) carrying brush contacts that are intended to make electrical connections to the microcircuit of the card, this frame (1) being covered by a cover (3), and a slot (4) being made between the frame (1) and the cover (3) in order to insert the card into the connector. Springy means (5) are placed between the cover (3) and the frame (1), these means being able to rub against the card as it is being inserted and to exert a greater force on the card than that exerted by the brush contacts (2).

Description: Connector for a card reader able to accept different card thicknesses The present invention relates to a connector for a microcircuit-card or smart-card reader comprising a frame carrying brush contacts that are intended to make electrical connections to the microcircuit of the card, this frame being covered by a cover, a slot being made between the frame and the cover in order to insert the card into the connector. Such a connector has been described, for example, in French Patents Nos . 87/15739 and 95/06854. It is known that microcircuit cards or smart cards may, given the recent developments aimed at making them increasingly secure, have various thicknesses ranging between 0.68 mm and 1.68 mm. When the slot for inserting the card into the connector allows a card of the maximum thickness to be inserted, the contact brushes bear on the contact pads of the microcircuit with a suitable force, thus ensuring that there is an excellent electrical connection to these pads. Thus the same does not apply in the case of thinner cards . This is because, in this case, the contact brushes do not flex sufficiently during insertion of the card so that the quality of the electrical connection to the contact pads of the microcircuit becomes insufficient. The object of the present invention is to overcome this problem. Thus, the subject of the invention is a connector for a microcircuit-card or smart-card reader, comprising a frame bearing brush contacts intended to make electrical connections to the microcircuit of the card, this frame being covered by a cover and a slot being made between the frame and the cover in> order to insert the card into the connector. According to the invention, this connector is characterized in that springy means are placed between the cover and the frame, these means being able to rub on the card as it is being inserted and to exert a greater force on the card than that exerted by the brush contacts . According to the invention, the springy means allow the card to be pressed against the contact brushes of the card, thus ensuring that there is an excellent electrical connection between the contact pads of the microcircuit of the card and the contact brushes, whatever the thickness of the card. Thus, the deformation of the springy means compensates for the various card thicknesses . Preferably, the said springy means are shaped so as to be able to deform as the card is being inserted and to generate a friction force on the card which is low enough not to increase the force for inserting the card into the connector. Thus, the presence of these springy means is no impediment to the card user. According to a preferred version of the invention, the springy means comprise at least one springy blade bearing on the card. Preferably, the springy blade is fixed by one of its ends to part of the cover or of the frame which is opposite the card insertion slot. Other features and advantages of the invention will also appear in the description below. In the appended drawings given by way of non- limiting examples : Figure 1 is a perspective view of the connector for a card reader ; Figure 2 is a perspective view of the contact- carrying frame and also of the springy metal blade of the connector ; Figure 3 is a perspective view of the cover of this metal blade ; and Figure 4 is an exploded view showing the insulating brush-carrying frame, the springy blade, the cover and two cards of different thicknesses. Referring to the appended drawings, the connector for a smart-card reader comprises a frame 1 made of insulating material carrying brush contacts 2 that are intended to make electrical connections to the microcircuit of the card. This frame 1 is covered by a cover 3, also made of insulating material. A slot 4 is made between the frame 1 and the cover 3 in order to insert the card into the connector. According to the invention, springy means 5 (see Figures 2, 3 and 4) are placed between the cover 3 and the frame 1, these means being able to rub against the card 6 or 6a as it is being inserted and to exert a greater force on the card than that exerted by the brush contacts 2. The springy means 5 are shaped so as to be able to deform as the card is being inserted and to generate a friction force on the card which is low enough not to increase the force for inserting the card into the connector . The springy means 3 comprise at least one springy blade 7 which bears on the card, this springy blade 7 being fixed by one of its ends to part of the cover 3 or of the frame 1 which is opposite the slot 4 for inserting the card 6 or 6a. The other end of the blade is slightly bent towards the cover so as to define a surface 7a of rounded shape for bearing on the card (see Figure 2) . In the example shown, the springy means 5 comprise two blades 7 parallel to the direction of insertion of the card so as to be able to rub against the card 6 or 6a close to its longitudinal edges. In the example illustrated, the two blades 7 are linked at one of their ends by a transverse blade 8 which has tabs 9 for fastening it to the cover 3. The combination formed by the two blades 7 and the transverse blade 8 is produced as a single piece by cutting it out from a sheet of springy metal . The device that has just been described operates in the following manner : When inserting quite a thick card into the slot-shaped opening 4, the upper and lower surfaces of the card come into contact with the brush-carrying frame 1 and the lower part of the cover 3. This card will therefore pass beneath the springy member 5 which has a ramp on each of the two blades 7, thereby allowing correct and compliant insertion of the card. Because these ramps make a small angle with the plane of insertion of the card, a flexure of the springy member and a forward movement of the two blades, the latter remaining pressed against the cover, are obtained. Since the rear of the springy blades cannot move, being in abutment against the walls of the cover and held in place by tabs each housed in a slot, the result is that the springy blades can flex and move towards the front of the connector. When inserting a thick card, this difference in thickness compared with a card of minimum thickness causes the springy blades to deform and exert a greater force on the card than that exerted by the brush contacts in order to guarantee a good-quality electrical contact. The springy blades also serve as brakes for the card in the connector in order to avoid the various vibration problems. In the case of inserting a relatively thin smart card into the slot -shaped opening 4, the lower and upper surfaces of the card come into contact either with the brush-carrying frame 1 or with the lower part of the cover 3. Consequently, the card passes beneath the ramps 7a of the springy blades 7, which make it easier for the card to enter. When using a thin card, the springy blades remain rigid and insertion of the card causes the brush contacts 2 to flex, the latter thus guaranteeing correct contact with the pads of the smart card.

Claims: CLAIMS 1. Connector for a microcircuit-card or smart- card reader comprising a frame (1) carrying brush contacts (2) that are intended to make electrical connections to the microcircuit of the card, this frame (1) being covered by a cover (3) , and a slot (4) being made between the frame (1) and the cover (3) in order to insert the card into the connector, characterized in that springy means (5) are placed between the cover (3) and the frame (1) , these means being able to rub against the card as it is being inserted and to exert a greater force on the card than that exerted by the brush contacts (2) . 2. Connector according to Claim 1, characterized in that the said springy means (5) are shaped so as to be able to deform as the card is being inserted and to generate a friction force on the card which is low enough not to increase the force for inserting the card into the connector. 3. Connector according to either of Claims 1 and 2, characterized in that the springy means (3) comprise at least one springy blade (7) bearing against the card. 4. Connector according to Claim 3, characterized in that the springy blade (7) is fastened by one of its ends to part of the cover (3) or of the frame (1) which is opposite the slot (4) for inserting the card. 5. Connector according to Claim 5, characterized in that the other end of the blade and slightly bent towards the cover so as to define a surface (7a) of rounded shape for bearing on the card. 6. Connector according to any one of . Claims 3 to 5, characterized in that springy means (3) comprise two blades (7) parallel to the direction of insertion of the card, so as to be able to rub against the card close to its longitudinal edges. 7. Connector according to Claim 6, characterized in that the two blades (7) are linked at one of their ends by a transverse blade (8) which has means (9) for ensuring that it is fastened to the cover (3) . 8. Connector according to Claim 7, characterized in that the combination formed by the two blades (7) and the transverse blade (8) is made as a single piece by cutting it out from a sheet of springy metal .

Inventors: BERNARDET JEAN-BAPTISTE, BERNARDET, JEAN-BAPTISTE
Applicants: BERNARDET JEAN BAPTISTE, FRAMATOME CONNECTORS INT, BERNARDET, JEAN-BAPTISTE, FRAMATOME CONNECTORS INTERNATIONAL
Application year: 1998
Main classification: G06K7
IPC codes: G06K7