Patent Publication Number: US-6036511-A

Title: Card connector

Description:
FIELD OF THE INVENTION 
     This invention relates to card connectors receiving memory cards and other types of cards equipped with a means of card ejection. 
     BACKGROUND OF THE INVENTION 
     An example of a card connector of such a type can be found in Japanese Utility Model Publication No. 92-86970 and Japanese Utility Model Publication No. 93-75974. Both card connectors described in these publications have a cam member mounted in a rotational manner in the housing accommodating the card and a sliding lever linked to the cam member. In these card connectors, the cam members can be rotated by pushing the lever in an assigned direction, thus causing the ejection of the card inserted in the connector. In the second card connector, a spring is provided which at all times applies spring force to the lever in the direction opposite to the direction the lever is pushed to eject the card. 
     However, the above card connectors needed improvements because they had relatively complicated structure and were difficult to assemble. Therefore, the purpose of the present invention is to offer a card connector having less complicated structure and an easier assembly process. 
     SUMMARY OF THE INVENTION 
     The present invention comprises a card connector including a cam member mounted in a rotational manner in a housing accommodating a card intended for the ejection of the card by means of cam member rotation wherein a recess is provided in the housing and opens to a side of the housing, the purpose of the recess is to house the cam member, a cantilevered arm is provided overlapping the recess and is pressed and bent into the recess by the cam member when the cam member is mounted in the recess and which returns to its initial position when the cam member reaches its prescribed position, thus locking the cam member in place while making it possible for the cam member to rotate in the recess. 
     It is preferable that the recess has an opening oriented perpendicularly to an outside surface of the housing and that its rear portion is of a curved configuration. Before the insertion of the cam member, the cantilever arm extends so that its free end overlaps the recess. The free end of the cantilever arm locks the cam member in place while making it possible for it to rotate. 
     In addition, the present invention is directed to a card connector having a cam member mounted in a housing accommodating the card, a lever engaged with the cam member can slide relative to the housing and move the cam member when the lever is slid in a predetermined direction, thus ejecting the card, and a spring connected to the lever which at all times presses the lever in the direction opposite to the predetermined direction, wherein the spring is a metal wire and is secured in the housing in the direction which is substantially perpendicular to the sliding direction of the lever. 
     The metal wire is mounted along a forward edge of the housing forming a cantilevered configuration. The wire can be mounted in a deformed condition and is arranged in such a manner that it continuously exerts pressure on the lever. The metal wire has an axle bent at a right angle which is disposed in an opening in the housing. The metal wire is supported at least at two locations along its longitudinal length. The wire can be a steel piano wire. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Embodiments of the present invention will now be described by way of example with reference to the accompanying drawings in which: 
     FIG. 1a is a top plan view of a card connector of the present invention showing a lever in a rearward position. 
     FIG. 1b is a view looking from the bottom of FIG. 1a. 
     FIG. 1c is a view looking from the right of FIG. 1a. 
     FIG. 2a is a top plan view of the card connector of FIG. 1a showing the lever in a forward position. 
     FIG. 2b is a view looking from the bottom of FIG. 2a. 
     FIG. 2c is a view looking from the right of FIG. 2a. 
     FIG. 3 is a top plan view of the card connector of FIG. 1a showing the card connector in a first stage of assembly. 
     FIG. 4a is a top plan view showing a spring member used in the card connector. 
     FIG. 4b is a view looking from the bottom of FIG. 4a. 
     FIG. 5a is a top plan view of the card connector of FIG. 1a showing the completion of the first stage of assembly and preparation for the second stage of assembly. 
     FIG. 5b is a bottom view of FIG. 5a. 
     FIG. 6a is a top plan view showing the completion of the second stage of assembly. 
     FIG. 6b is a bottom view of FIG. 6a. 
     FIGS. 7a-7d are respective views of a cam member with FIG. 7a being a top plan view, FIG. 7b is a view looking from the bottom of FIG. 7a, FIG. 7c is a bottom view of FIG. 7a, and FIG. 7d is a view looking from the right of FIG. 7c. 
     FIG. 8 is a part top plan view of the card connector showing the first stage of assembling the lever thereto. 
     FIG. 9 is a view looking from the right of FIG. 8 showing a second stage of assembling the lever to the card connector. 
     FIG. 10 is a view similar to FIG. 8 showing the third stage of assembling the lever to the card connector. 
     FIG. 11 is a view similar to FIG. 10 showing the fourth stage of assembling the lever to the card connector. 
     FIG. 12 is a cross-sectional view taken along line 12--12 of FIG. 10. 
     FIGS. 13a-13d are respective cross-sectional views taken along lines 13a--13a, 13b--13b, 13c--13c, and 13d--13dof FIG. 1b. 
     FIG. 14a is a top plan view of an alternative embodiment of the card connector. 
     FIG. 14b is a view looking from the bottom of FIG. 14a. 
     FIG. 15a is a top plan view of a spring member used in the card connector shown in FIGS. 14a, 14b. 
     FIG. 15b is a view looking from the bottom of FIG. 15a. 
     FIG. 16a is a bottom view of a card connector wherein the housing has basically the same configuration as that of the card connector shown in FIG. 14a. 
     FIG. 16b is a view looking from the bottom of FIG. 16a. 
     FIG. 17a is a top plan view of a spring member used in the card connector shown in FIGS. 16a, 16b. 
     FIG. 17b is a view looking from the bottom of FIG. 17a. 
     FIG. 18 is a top plan view of an alternative embodiment of the cam member. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As it is clear from FIGS. 1-13, card connector 10 has multiple electrical contacts 15 and a dielectric housing 30 in which the contacts are arrayed. As can be seen from FIGS. 1a-1d, the housing 30 has a card-receiving section 31 into which memory cards can be inserted. In the card-receiving section 31, contact sections 17 of contacts 15 are arranged. The card connector 10 is designed for flash memory cards or other memory cards. The card connector 10 is intended for mounting on printed circuit boards (not shown) for which purpose the connector has holes 32 for mounting screws. In addition, auxiliary reinforcing fixtures 40 are provided on sides 33a, 33b of the housing 30 the purpose of which is to make mechanical connection to the circuit board more reliable. Multiple contacts 15 and auxiliary reinforcing fixtures 40 have soldering sections 16 and 41 respectively for soldering to the board by SMT technology. They are soldered to soldering pads prepared on the printed circuit board (not shown). 
     The card connector 10 also has an ejection mechanism for the ejection of a card (not shown) inserted in the card-receiving section 31 of the connector. The ejection mechanism includes a lever 50 arranged so that it can slide along the side 33b, a cam member 70 secured to the housing 30 in a pivoting manner and a linear spring 90 of spring metal wire. Configurations of all parts are discussed in detail below. 
     Operation of the ejection mechanism can best be understood by following movements of all parts as shown in FIGS. 1a-1c and 2a--2c. The cam member 70 has an ejection leg 71 pressing against a card edge. When the cam member 70 is rotated, the ejection leg 71 presses on the card, thus ejecting it outside the connector. The cam member 70 is engaged with the lever 50 (for details, see below). Therefore, when the lever 50 is pressed in the forward direction (shown in FIG. 1a by arrow P), the cam member 70 is rotated causing card ejection. The spring 90 presses on the lever 50 in the opposite direction and after the card has been ejected, it returns the lever 50 from the position shown in FIG. 2a to its initial position shown in FIG. 1a. Below, the assembly of the card connector 10 will be explained. 
     The first stage of assembly involves the installation of the spring 90 on the housing 30 with multiple electrical contacts secured therein. Since contacts 15 are fixed by a commonly-known method by pressing them in the housing, description thereof is omitted. The spring 90 mounted on the housing 30 can be made of a steel wire, for example, a piano wire. In this embodiment, it is made of SWP-A grade piano wire. As shown in FIGS. 4a, 4b, one end 91 of the spring 90 which is intended for the connection to the lever 50 is obliquely bent. The other end is bent substantially perpendicular to the direction of the bent end 91, thus forming a pivot 92. Housing 30 has an opening 39a into which the pivot 92 is inserted and retained, a lug 39b at some distance from the opening 39a supports the spring 90 from the other side and another lug 39c located near the end 91 of the spring 90 is intended for a temporary support of the spring. These retaining means are along a front end of the housing 30. The mounting of the spring 90 begins with the pivot 90 being inserted in the opening 39a. After that, the spring 90 can freely rotate around the opening 39a as the center of rotation. Next, the spring 90 is placed over a wall 89 of the housing 30 on the card insertion side 31. This state is shown in FIG. 3. The spring 90 is rotated in a direction indicated by arrow R. The spring 90 is moved in this direction sliding along the wall 89 until it reaches retaining lug 39b and temporary retention lug 39c. When the spring 90 is in a position nearly overlapping these retention means, it is pressed downward so that it is engaged with lugs 39b and 39c. As can be seen from FIG. 5a, the spring 90 is reliably secured and only slightly deformed by retention points at the opening 39a, lug 39b and temporary retention lug 39c. 
     The second stage of the assembly involves the installation of the cam member 70 in the housing 30. Configuration of the cam member 70 is shown in FIGS. 7a-7d. Cam member 70 has a flat base section 74, pivot members 72a, 72b extending up and down from approximately the center of the base section 74, and engaging sections 73a, 73b extending up and down from one end of the base section 74. The engaging sections 73a, 73b are intended for engagement with the lever 50 according to the explanation below. On the end of the base section 74, which is opposite to the end where the engaging sections 73a, 73b are located, a card-ejection section 71 is located. The pivot members 72a and 72b are of the same size and have a symmetrical configuration. The engaging sections 73a, 73b are not symmetrical in the vertical direction, but surfaces 76, 77 are common for both members and they connect together connecting sections 73a, 73b forming an engaging end 78. An especially important feature is the surface 75 of the engaging section 73b, the purpose of which is explained below. 
     When the cam member 70 is installed, it is moved in the direction shown by arrow X in FIGS. 5a, 5b. As can be seen, a recess 21 is formed at the edge of the top wall 89 of the housing 30, so that its opening is substantially perpendicular to the side 33b and the rest of the recess 21 is curved toward the front end of the housing. The recess 21 is in communication with the space 38 linked to the card-receiving section 31. In the lower part of the space 38, a cantilevered arm 36 is located so that its end extends into the recess 21 toward the rear of the card-receiving section 31. During assembly, the base section 74 of the cam member 70 is inserted in the space 38 so that the pivot member 72a is aligned with the recess 21. At this time, the pivot member 72b is located at the same level as the arm 36. Therefore, in order to insert the cam member 70 in the housing 30, it is necessary to advance the pivot member 72a inside the recess 21 so that contact is formed between the pivot member 72b and the arm 36. When the cam member 70 is advanced further, the arm 36 is bent inward in the direction indicated by arrow Q (see FIG. 5b) so that the pivot member 72a can be advanced even further inside recess 21. Since as mentioned above recess 21 is curved toward the rear, the pivot member 72a is guided toward the rear along the curve. When the pivot member 72a reaches the predetermined position, that is the deepest part of the recess 21, the engagement between the pivot member 72b and the arm 36 is discontinued, and the arm 36 returns to its initial non-bent position and its end 35 locks the pivot member 72b in place in recess 21. Therefore, cam member 70 is secured in position in the housing 30 as shown in FIGS. 6a, 6b so that it can rotate. Arrow S indicates directions in which the cam member can rotate. 
     The third stage of the assembly involves the installation of the lever 50. The steps of the lever installation are shown in FIGS. 8-12. 
     The configuration of the lever 50 can be seen in FIGS. 8, 9 and 12. The lever 50 includes a mounting extension 51 for attachment of an operating button, a main body 52 and a connecting section 53 for engagement with the cam member 70. The operating button is not shown in the drawing, but any type of button according to the customer needs can be affixed to the mounting extension 51. An inside surface 52a of the main body 52 facing the housing 30 has a step 54 extending therealong. The step 54 has a catch 55. At two locations along the length of the inside surface 52a, slots 56a, 56b are located. The slot 56a is wider than the slot 56b. As shown in FIG. 12, the main body 52 has an L-shape cross section, and as can be seen from FIG. 9, a slot 57a in communication with an opening 57b is formed in the longitudinal direction of the outer surface 52b of the main body 52. It should be noted that, as shown in FIG. 9, the opening 57b is opened downward. Thus, slot 57a and opening 57b form an L-shape. The connecting section 53 has a contact surface 58 which engages with the contacting end 78 of cam member 70, and an extension 61 protruding forward from an upper portion of the contact surface 58. As shown in FIGS. 8, 9, a groove 62 is located in a front end of the extension 61. From FIG. 9, it can be seen that the groove 62 has a U-shape profile and extends along the edge of the front end of the extension 61. The operation of this arrangement is explained below. 
     According to FIG. 8, on the side 33b of the housing 30 to which the lever 50 is to be attached, keys 37a, 37b of different widths are located. An L-shaped lever-supporting arm 36 fits between keys 37a, 37b. Near the center of the inner side of the lever-supporting arm 36, a rib 36a is located (see FIG. 12). 
     During the first stage of assembly, the lever 50 is placed relative to the housing 30 as shown in FIGS. 8, 9. As shown in FIG. 8, the lever 50 is positioned so that keys 37a, 37b and key slots 56a, 56b are aligned; then the lever 50 is moved in the direction shown by arrow A so that it overlaps the lever-supporting arm 36. 
     During the second stage of assembly, the lever 50 is moved in the direction indicated by arrow B (FIG. 9) so as to be attached to the side 33b of the housing 30. At this time, if the parts are aligned correctly during the first stage of assembly, keys 37a, 37b are inserted in the slots 56a, 56b, thus making it possible to move the lever 50 to a predetermined height. During this movement, the rib 36a is disposed within the opening 57b in the outer surface 52b of the lever 50. When the lever 50 reaches the predetermined position, the rib 36a is at the top of the opening 57b (see FIG. 9) in alignment with slot 57a. 
     During the third stage of assembly, the lever 50 is moved in the direction shown by arrow C in FIGS. 9, 10, that is it is pushed forward. At the end of this movement, the lever 50 reaches the extreme forward position. In this position, rotation of the cam member 70 is blocked due to contact between the surface 75 of the cam member 70 and the side 33b of the housing 30 (see FIGS. 7, 8). The blocking action of the cam member 70 caused by the contact between the surface 75 and the side 33b takes place not only during the mounting of the lever 50 but every time during card ejection. As shown in the drawings, in the extreme forward position of the lever 50, the groove 62 in the end of the lever 50 and the end 91 of the spring 90 are engaged and the spring 90 is bent back. 
     During the fourth stage of assembly, the pressure applied to the lever 50 in the direction indicated by arrow C is relieved. This results in a force applied to the lever 50 by the spring 90 in the opposite direction indicated by arrow D in FIG. 11. At that time, as shown in FIG. 11, the catch 55 is engaged with the shoulder 39 of the key 37a, thus preventing the lever 50 from further movement in the direction indicated by arrow D. It should be noted that at this time the spring 90 is only slightly deformed. As a result of the operations described above, the lever 50 becomes movably mounted on the housing 30, thus completing the assembly of the card connector 10. In this state, the cam member 70 can freely rotate to any position, for example to the position shown in FIG. 11. However, when a card is inserted in the card connector 10, the card engages against the ejection section 71 thereby turning the cam member 70. When the card is fully inserted, the cam member 70 assumes the position shown in FIG. 1 in which the card is in contact with the ejection section 71, thus enabling ejection of the card. 
     As can be seen from FIGS. 13a-13d, multiple contacts 15a -15f are arranged in the connector for sequential connection. Contact pairs 15a, 15b shown in FIGS. 13a-13c, located at the sides of the connector and contact pair 15a, 15b located in the center of the connector have long contact sections 16a, 16b, and they are used for power supply. Contact pair 15c, 15dshown in FIGS. 13a, 13chave the short contact sections 16c, 16d; they are used for the detection of the card position. Typical contacts 15e, 15f shown in FIG. 13d have contact sections 16e, 16f of an intermediate length between lengths of contact sections 16a, 16b and 16c, 16d. Contacts 15e, 15f are used for the transmission of signals. All contacts 15a-15f have post sections 18a-18e, including surface mounting sections 17a-17e. Tie-ins 18a-18e are brought out from the housing 30 through slots 81 made in the back wall of the housing and are arranged in one row. As can be seen from FIG. 13a, slots 81 have an oblique surface 82 whose top edge is separated from the post sections 18a-18e, and whose lower edge 84 is located closer to the post sections 18a-18e. Such a configuration is provided to compensate for allowances made during assembly. 
     FIGS. 14-17b show an alternative embodiment of the card connector according to this invention. 
     The difference between card connectors 110, 110&#39; of the alternative embodiment of this invention shown in FIGS. 14-17b and the card connector 10 is mostly in the way the spring is secured on the housing and in the configuration of the spring. As can be seen from FIGS. 14a, 14b, 16a, 16b, card connectors 110, 110&#39; differ by the side to which the ejection cam member 170, 170&#39; is mounted. Card connectors 110, 110&#39; have pairs of openings 139a, 239a and 139a&#39;, 239a&#39;; pairs of lugs 139b, 239b and 139b&#39;, 239b&#39; and pairs of temporary retention lugs 139c, 239c and 139c&#39;, 239c&#39;. Housings 130, 130&#39; also have on both their sides matching recesses 121, 221 and 121&#39;, 221&#39;. Similar to the connector shown in FIG. 1, connectors depicted in FIGS. 14 and 17 have levers engaged with cam members 170, 170&#39; which are arranged along side 133b, 133b&#39; of the housings 130, 130&#39; (these levers are not shown in FIGS. 14 and 17). As can be seen from the plan view of the springs 190, 190&#39; for card connectors 110, 110&#39;, they are not straight. The first oblique sections 191, 191&#39; and the second oblique sections 192, 192&#39; form bulges facing forward. 
     The advantage of structures shown in FIGS. 14 and 17 is that the same metal parts can be used in both of the housings 130 and 130&#39;. The difference between the housings 130, 130&#39; is that slots for the lever-supporting arms 186, 186&#39; are formed on different sides of the housings. Therefore, lever-supporting arms 186, 186&#39; can be used interchangeably in either of the housings 130, 130&#39;. This makes it possible for the customers to quickly change configuration of equipment to better suit their preferences. The purpose of bulged sections of springs 190, 190&#39; formed by oblique sections 191, 191&#39; and 192, 192&#39; is to extend along lugs 239b, 139b, which are not used in the selected configuration, thus making it possible to modify connectors. 
     Above, explanations concerning embodiments of card connectors according to this invention have been provided, which are used as examples and do not limit the scope of the invention in any way; it is a matter of fact that changes and modifications can be introduced by experts in the field. As an example of possible modifications, it is possible to use a cam member 70&#39; shown in FIG. 18. The specific feature of the cam member 70&#39; is that the pivot 72&#39; has an oval rather than round cross section, and that on the right side R the curvature is smaller (that is, the radius of the curve is larger) than on the left side L. Because of such configuration, card ejection can be initiated by a shorter stroke of the lever but the ejection will require a greater effort at the beginning which will decrease as the ejection progresses. This results in a smoother operation of the card-ejection mechanism. 
     The first specific feature of the card connectors according to this invention is that a recess is formed in the housing with an opening to a side of the housing and a cantilevered arm overlaps the recess. When the cam member is mounted through the opening in the side of the housing, the cantilevered arm is bent, and when the cam member reaches its predetermined position, the cantilevered arm returns to its initial position locking the cam member in place while allowing it to rotate, thus making it possible to simplify the installation of the cam member which is an essential part of the card-ejection mechanism. Such a structure makes it possible to implement assembly by automatic machinery. The second specific feature of the card connectors according to this invention is that a spring provides at all times pressure to a lever in the direction opposite to that of its insertion, it is made of a metal wire; and, due to the fact that it is mounted on the housing practically perpendicular to the direction of the sliding motion of the lever, spring configuration is substantially simplified and its installation is much easier. Such a configuration provides for an easy linking of the spring to the lever.