WO1998024045A1

WO1998024045A1 - eMART CARD CONNECTOR

Info

Publication number: WO1998024045A1
Application number: PCT/IB1997/001468
Authority: WO
Inventors: Paul Lindeberg
Original assignee: The Whitaker Corporation
Priority date: 1996-11-27
Filing date: 1997-11-20
Publication date: 1998-06-04
Also published as: AU4792597A

Abstract

A smart card connector is provided with a pivotable actuator (38) stamped and formed from sheet metal and integrally comprising a spring (48), a mounting portion (46), and a card detection switch (72). Prior to card insertion, the actuators (38) depress the contacts (10) out of the card receiving slot (16). Full insertion of the card causes engagement with a camming portion (64) of the actuator which pivots and releases the contacts that bias against the card. Stamping and forming the actuator with spring and mounting portion integrally from sheet metal enables provision of a slim, robust connector which is also cost-effective to assemble.

Description

SM7ART CARD CONNECTOR

This invention relates to a connector for contacting a chip card, also called smart card or integrated circuit (IC) card, where means are provided for reduced contact wear.

In European Patent 468 828, a smart card connector is described comprising an insulative housing and two rows of cantilever beam resilient contacts with contact protrusions proximate their free ends for engagement against a card introduced in a slot of the housing. In order to reduce contact wear, the contacts, which would normally bias into the card receiving slot, are pressed downwardly by a rocker pivotly mounted to the housing and having shoulders at one end engaging the contact free ends, the other end of the rocker being biased by a coil spring. The coil spring biases the rocker such that contact free ends are depressed. When a card is almost fully inserted into the slot, it engages a camming surface proximate the spring end of the rocker, such that the rocker is pivoted and the engagement end releases the contacts which bias against the card for electrical contact therewith. The rocker is mounted in the housing by means of studs clipped into corresponding grooves of the housing. The rocker is typically a part moulded from plastic.

There are a number of inconveniences to this design. Firstly, the provision of the pair of coil springs for biasing the rocker renders the connector expensive to manufacture and assemble. Furthermore, in order to provide the rocker with sufficient structural rigidity as it is moulded from plastic, it is a relatively bulky (thick) component. In addition, the pivot support is subject to friction and wear, and is therefore prone to malfunctioning, damage or inaccurate positioning. The rocker cam may also be subject to excessive wear by abutment with card edges. The latter problems arise especially where the connector is intended to be used for a large number of cycles or in unfavorable environmental conditions (e.g. large temperature changes, humidity) .

It would therefore be desirable to provide an improved smart card connector.

It is an object of this invention to provide an improved smart card connector that is compact, yet robust and adapted to reliably withstand a large number of connection cycles. It would be further advantageous to provide such a connector that is cost-effective to manufacture and assemble.

Objects of this invention have been achieved by providing the smart card connector according to claim 1. Disclosed herein is a smart card connector comprising a housing, a card receiving slot for receiving a card in an insertion direction, terminals having contact protrusions biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator for engaging the terminals such that the contact protrusions are biased out of the card receiving slot prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, wherein the actuator comprises a spring portion integrally formed therewith for rotatably biasing the actuator in the position prior to full insertion.

Objects of this invention have been achieved by providing the smart card connector according to claim 2. Disclosed herein is a smart card connector comprising a housing, a card receiving slot for receiving a card in an insertion direction, terminals having contact protrusions biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator for engaging the terminals such that the contact protrusions are biased out of the card receiving slot prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, characterized in that the actuator is stamped and formed from sheet metal .

Objects of this invention have also been achieved by providing the smart card connector according to claim 3. Disclosed herein is a smart card connector comprising a housing, a card receiving slot for receiving a card in an insertion direction, terminals having contact protrusions biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator for engaging the terminals such that the contact protrusions are biased out of the card receiving slot prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, characterized in that the connector further comprises a cover stamped and formed from sheet metal and mounted against a top face of the housing, wherein the card receiving slot is bounded by the cover and a guide surface of the housing.

Advantageously therefore, the smart card connector has a slim rocker mechanism that is also robust and cost- effective to manufacture and assemble particularly as few parts are required and attachment of the rocker to the connector is secure.

Further advantageous aspects of this invention will be apparent from the following description, drawings and claims. Embodiments of this invention will now be described by way of example with reference to the figures, in which;

Figure 1 is a cross-sectional view through a smart card connector according to this invention in the card receiving position; Figure 2 is a view similar to that of Figure 1 where the actuator is moved to a connected position, a card not being shown for more clarity;

Figure 3 is an isometric view of the smart card connector with a cover removed to show a card receiving face of the connector;

Figure 4 is a view similar to that of Figure 3 of a second embodiment; and

Figure 5 is an isometric view of the smart card connector with a cover.

Referring to Figures 1 and 3, a smart card connector 2 comprises a housing 4 and first and second rows 6,8 of terminals 10 securely mounted to the housing. The housing comprises a bottom face 12 and a top face 14 opposed and substantially parallel thereto, further comprising a card receiving slot 16 proximate the top face 14 and extending substantially parallel to the faces 12,14. An integrated circuit (IC) card (not shown) is receivable within the slot 16 at an entry end 17 for contacting the terminals 10 when fully inserted into the slot which extends up to a stop 18 in the form of a shoulder provide proximate a remote end 20 of the housing opposite to the entry end 17.

The card receiving slot 16 is formed by a card guide surface 22 of the housing 4 and an inner surface 24 of a cover 26 that is assembled to the housing as best seen in Figure 1 and 5. The cover 26 is stamped and formed from sheet metal such that a particularly slim connector is provided, whilst nevertheless ensuring a robust construction. The rows 6, 8 of terminals 10 are arranged in a substantially mirror image disposition, the terminals 10 of both of the rows being substantially identical, each comprising a connection section 28, in this embodiment for mounting to a printed circuit board, an attachment portion 30 extending therefrom secured to the housing 4, a cantilever spring portion 32, a contact protrusion 34, and a free end 36 which is proximate and facing the free end of the opposed aligned terminal of the other row. The connector further comprises a terminal actuator 38 comprising a lever arm 40 extending from a card engagement end 42 to a terminal engagement end 44 in the general direction of insertion (D) of a card in the slot 16. The terminal actuator 38 further comprises an attachment portion 46 for securely attaching the actuator to the housing 4, and a spring portion 48 extending between the attachment portion and the lever arm 40. The lever arm, spring portion and attachment portions are integrally formed, in this embodiment by stamping and forming the actuator 38 from sheet metal. The stamped and formed terminal actuator enables provision of a particularly slim terminal engagement mechanism that can be provided with an integral spring and robust attachment portion due to the high strength and resilience of selected sheet metals (for example stainless steel) . The attachment portion 46 comprises a stake (not fully shown) that is stitched into a corresponding cavity 50 of the housing 4. The stake may have retention barbs or other interference fit means for gripping within the housing cavity 50. The stake extends substantially perpendicular to the housing faces 12,14,22 such that the actuator 38 can be assembled, for example in an automated manner, from the top face 14 in a single stitching movement i.e. orthogonal to the plane of the connector surface 12 or 14. By assembling the various components of the connector from a top face 14, assembly of the connector is simplified, thereby substantially reducing the manufacturing cost thereof. In the embodiments shown, all the components can be assembled to the connector from a single side i.e. the top face 14. The spring portion 48 is substantially planar, as is an extension 47 of the attachment portion 46, and a central portion 49 of the lever arm 40 such that a particularly low profile is achieved, which is also well suited for manufacturing the actuator from sheet metal . In order to provide sufficient resilience, the spring portion 48 is cut into a meandering form within the plane so as to form an S- shape between the lever arm and attachment portion. Other spring shapes are also possible as shown in embodiment of Figure 4 where the spring portion is in the form of a cantilever beam 48', the attachment portion 46' being positioned closer to the remote end 20' of the connector than the first embodiment according to Figure 3. The spring and attachment portion are positioned within a slight recess 52,52' below the card guide surface 22.

When the actuator 38 is mounted to the housing, the central portion 49 rests against a pivot stud 54 projecting from the base wall 5 of the housing and having an upper arcuate abutment surface 55 against which the lever arm is supported. The projection 54 thus enables rotation of the lever arm thereabout and is substantially centrally positioned between the lever arm camming end 42 and terminal engagement end 44. The terminal engagement end 44 of the lever arm is substantially planar and overlaps the terminal free ends 36 of both rows. The engagement end 44 is stamped below i.e. offset with respect to the lever arm central portion 49 by an oblique transition portion 56, such that in the disconnected position the engagement end 44 depresses the terminals away from the card receiving slot 16 whereby the contact protrusions 34 are at or below the level of the card guide surface 22. A card inserted in the slot 16 thus avoids rubbing the contact protrusions. At the actuator transition portion 56, is a cutout 58 to enable passage therethrough of the contact protrusions 34 of one of the rows 6.

In order to prevent short circuiting, an insulator or insulators 60 are provided between the actuator engagement end 44 and terminal free ends 36. In this embodiment, the insulators 60 are integrally moulded over the terminal free ends, but the insulator could also be attached to the actuator. Each of the contacts has its own overmoulded insulator 60 to allow independent movement of the contacts. The manufacturing of the terminal rows 6,8 can be effected in a cost-effective manner by overmoulding housing portions 62 about the terminal attachment portions 30, and overmoulding a single insulative housing portion over the free ends 36, which is then stamped to cut away insulative portions linking the contacts such that they are independent at their free ends . A terminal set corresponding to one of the rows 6, 8 is thus provided, which is then assembled to the housing 4 by heat bonding, or provision of interference retention means or any other conventional fixation means. The terminal sets of both of the rows 6, 8 can be made similar or possibly identical in order to further reduce costs.

The camming end 42 of the lever arm 40 has a raised oblique portion 64 projecting into the card receiving slot 16 proximate stop 18 for engaging an almost fully inserted card. As depicted in Figure 2, when the camming portion 64 is biased out of the card receiving slot 16 due to full insertion of a card (not shown in Figure 2) the lever arm 40 rotates about the pivot stud or support 54 thereby lifting the engagement end 44 such that the contact protrusions bias towards the card receiving slot 16. In Figure 2 the contacts are shown in their free standing, unstressed position where the contact protrusions extend into the card receiving slot 16. Obviously, when a card is present in the slot the contacts bias resiliently thereagainst, the contact protrusions 34 being at the level of the card guide surface 22.

It would also be possible to provide the actuator engagement end 44 below the contacts such that the contacts are biased positively against the card by action of the actuator, although, inter alia, for assembly purposes the embodiment according to Figures 1 and 2 is more advantageous . As shown in Figures 3 and 4, the actuator is further provided with a card detection switch mechanism 70 which comprises an extension 72 extending laterally from the camming end 42 of the actuator and having a contact 74 that is depressed against a complementary contact 76 mounted in the base wall of the housing. The actuator contact 74 may either simply depress against the contact 76 which is coupled to a switch, or electrically contact the contact 76 for electrical connection therebetween. In the latter case, the actuator is provided with a further electrical connection, which for example could be an extension of the actuator that contacts one of the terminals. The extension 72 acts as a resilient cantilever beam to provide a spring force for effective contact between the contacts 74,76. By stamping and forming the actuator 38 from sheet metal, the card detection mechanism is particularly cost-effective to produce due to the integral forming of the extension 72 which may also provide an electrical contact 74. The ability to mount the components from the connector top face, including mounting of the cover 26 is also particularly advantageous. The cover 26 stamped and formed from sheet metal may either be crimped to the housing or provided with resilient latches 78 that clip onto corresponding latch protrusions 80 provided on side walls metal cover 26 also provides effective shielding against electromagnetic and electrostatic interference if necessary (a ground connection to the cover is then provided) .

Claims

1. A smart card connector (2) comprising a housing (4) extending from an entry end (17) to an opposed remote end (20), a card receiving slot (22) extending from the entry end to a stop (18) proximate the remote end for receiving a card in an insertion direction (D) , terminals (10) having contact protrusions (34) biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator (38) for engaging the terminals (10) such that the contact protrusions (34) are biased out of the card receiving slot (22) prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, characterized in that the actuator comprises a spring portion (48) integrally formed therewith for rotatably biasing the actuator in the position prior to full insertion.

2. A smart card connector (2) comprising a housing (4) extending from an entry end (17) to an opposed remote end (20), a card receiving slot (22) extending from the entry end to a stop (18) proximate the remote end for receiving a card in an insertion direction (D) , terminals (10) having contact protrusions (34) biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator (38) for engaging the terminals (10) such that the contact protrusions (34) are biased out of the card receiving slot (22) prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, characterized in that the actuator is stamped and formed from sheet metal.

3. A smart card connector (2) comprising a housing (4) extending from an entry end (17) to an opposed remote end (20), a card receiving slot (22) extending from the entry end to a stop (18) proximate the remote end for receiving a card in an insertion direction (D) , terminals (10) having contact protrusions (34) biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator (38) for engaging the terminals (10) such that the contact protrusions (34) are biased out of the card receiving slot (22) prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, characterized in that the connector further comprises a cover (26) stamped and formed from sheet metal and mounted against a top face (14) of the housing, wherein the card receiving slot is bounded by the cover and a guide surface (22) of the housing (4) .

4. A smart card connector (2) comprising a housing (4) extending from an entry end (17) to an opposed remote end (20), a card receiving slot (22) extending from the entry end to a stop (18) proximate the remote end for receiving a card in an insertion direction (D) , terminals (10) having contact protrusions (34) biasable against a card inserted in the slot for electrical contact therewith, and a rotatable actuator (38) for engaging the terminals (10) such that the contact protrusions (34) are biased out of the card receiving slot (22) prior to full insertion of a card therein and biased against the card after full insertion for electrical contact therewith, characterized in that the actuator is made of an electrically conducting material, and an insulator (60) is positioned between an engagement portion (4) of the actuator and the terminals (10) .

5. The connector of any one of the preceding claims wherein the actuator comprises a card detection switch arm (72,74) integrally formed therewith.

6. The connector of any one of the preceding claims wherein the actuator is provided with one or more mounting portions (46) having extensions substantially orthogonal to a top face (14) of the connector which is substantially parallel to the insertion direction such that the actuator can be mounted from the top face of the connector by stitching or insertion of the mounting portion extensions into corresponding cavities (50) of the housing.

7. The connector of any one of the preceding claims wherein the actuator comprises a lever (40) extending between a camming portion (42,64) projecting into the card receiving slot prior to full card insertion and an engagement end (44) biasable against the terminals (10), the lever (40) resting against a pivot stud (54) projecting up from a base wall (5) of the housing, the pivot stud acting as a support for rotation of the lever arm therearound.

8. The connector of any one of claims 1, and 3-7 wherein the actuator is stamped and formed from sheet metal.

9. The connector of any one of claims 1, 2 and 4-7 wherein the connector further comprises a cover (26) stamped and formed from sheet metal and mounted against a top face (14) of the housing, wherein the card receiving slot is bounded by the cover and a guide surface (22) of the housing (4) .

10. The connector of any one of claims 1, 2, 3 and 5-7 wherein the actuator is made of an electrically conducting material, and an insulator (60) is positioned between an engagement portion (4) of the actuator and the terminals (10) .