WO1996037091A1

WO1996037091A1 - Rigid pcmcia frame kit

Info

Publication number: WO1996037091A1
Application number: PCT/US1996/004618
Authority: WO
Inventors: Michael Paul Derstine; Randy Gray Simmons; Henry J. Persia
Original assignee: The Whitaker Corporation
Priority date: 1995-05-17
Filing date: 1996-04-04
Publication date: 1996-11-21
Also published as: JP2000514240A; EP0823194A1

Abstract

This invention is directed to a PCMCIA frame kit having improved stability, where the kit is intended to receive a planar electronic device for electrical engagement with a complementary device in electronic equipment. The kit comprises a pair of matable, metal cover members (12, 14), where each cover member is integrally molded to a dielectric frame (16, 40) upon which the planar electronic device is seated. The improved feature is the provision of each frame including at least a pair of side rails, where at least one side rail pair on one cover member includes plural, circular, upstanding pins (24) having a predetermined diameter, the matable side rail on the other cover member includes a like plurality of holes (62) to receive a corresponding pin. In a preferred embodiment, the cross section of holes exhibits a multi-sided configuration with the diametrical distance between opposing corners being slightly greater than the predetermined diameter, and the diametrical distance between opposing sides is slightly less than the predetermined diameter. By this arrangement a normal force applied between the covers effects a force fit between each respective pin and its multi-sided hole.

Description

RIGID PCMCIA FRAME KIT

This invention is directed to an improved PCMCIA frame kit that is easy to assemble, while providing structural integrity to the frame kit and protection to the contained planar electronic device, such as a conventional memory card.

Printed circuit (PC) cards containing external memory and data to be used in computer processes are known. The cards come in standard types defined by the Personal Computer Memory Card International Association (PCMCIA) . Such cards are housed in a memory card holder or frame kit which comprises a casing or frame made of an insulting material for receiving the printed circuit board, metal shielding covers, and at least one connector, typically referred to an "I/O" connector. The connector is provided on one end of the casing or frame for interfacing the memory card, and particularly the printed circuit board contained in the casing, to the computer equipment to which the card is mated. The connector is designed to extract the contents of the memory stored on the printed circuit board and to bus data to and from an outside environment, which also usually comprises a computer or other electronic equipment. In this fashion, data traverses the interface between the PC card and the outside environment so that the data can be efficiently transferred and used by the computer to which the card is mated for its intended purpose. PC cards are generally interchangeable and can be used with many different machines and electronic components. Because the PC cards are interchangeable, they undergo a significant amount of abuse when transported, interfaced and mated to the different computers and electronic equipment which use them.

Since a PC card is conventionally made up of a number of layers and/or elements glued or otherwise bonded together, the individual layers tend to become loose and/or separated from one another as the memory card is subjected to flexing or torsional stresses, as may occur when the card is inserted into or removed from the electronic or other computer-type equipment. Thus, even after moderate amounts of usage, conventional memory cards have heretofore frequently become structurally loose, and the internal members of the card often become misaligned. This results in failure of the PC card and degrades the performance of the electronic equipment which uses the card. These undesirable results generally induce poor performance of the computer system which uses the memory card. In U.S. Patent No. 5,339,222, there is disclosed a memory card holder that provides structural integrity to the assembly by the use of a pair of interfitting metal sheet-like cover members. Additionally the invention thereof provides continuous shielding against distortion of data signals between the PC or memory card and the I/O connector.

In a recent patent, U.S. Patent No. 5,397,857, there is disclosed a memory card package which includes a pair of stamped and formed metal covers, each secured to a plastic frame element. The plastic frame element is injection molded around a plurality of fingers which extend from the periphery of the respective cover member. Further, the plastic frame element extends beyond the plane of the metal cover to expose a perimeter. By this arrangement, apparent bonding of the two covers is facilitated, where a preferred manner of bonding is by sonic welding.

The prior art devices suffer from a lack of torsional rigidity. The problem to be solved by the present invention is that torsional twisting must be reduced and the device must be simple to manufacture. This invention relates to a stable and rigid PCMCIA frame kit for receiving a memory card, as known in the art, for electrical engagement with electronic equipment, such as a computer. The frame kit consists of a pair of matable, shielding cover members, where each cover member is integrally molded to a dielectric frame upon which the memory card is seated. The improved feature hereof is the provision of each frame including at least a pair of side rails, where the pair of side rails on one cover member includes plural, circular, upstanding pins having a predetermined diameter, and the pair of side rails on the other cover member includes a like plurality of holes. The cross section of the holes exhibit a multi-sided configuration with the diametrical distance between opposing corners being slightly greater than predetermined diameter of the pins, and the diametrical distance between opposing sides is slightly less than the predetermined diameter. By this arrangement, when a normal force is applied between the respective cover members a force fit is achieved between a respective pin and its multi-sided hole. In a preferred embodiment, the multi-side hole is a hexagon. Further, as an optional feature to enhance the stability of the frame kit, provision is made for localized sonic welding at the respective pin and hole locations by utilizing what is called a shear joint. Alternatively, the respective cover members may be essentially identical in construction, where each cover member includes pins along one side and sockets or holes along the opposite side. By flipping one cover member relative to the other, mating can be achieved, where the pins of one cover member are caused to engage corresponding sockets or holes in the other. The invention will now be described by way of reference to the drawings, where:

FIGURE l is a perspective view of a preferred embodiment of a PCMCIA frame kit incorporating the features of this invention;

FIGURE 2 is an exploded perspective view of the pair of cover members forming the frame kit of Figure 1, illustrating further, for example, details of the lower cover member along an interfacing edge surface; FIGURE 3 is an exploded perspective view similar to Figure.2, but showing details of a complementary interfacing edge surface of the upper cover member, for example, and a prepositioned memory card with I/O connector for receipt in the frame kit; FIGURE 4 is a partial, longitudinal sectional view taken along line 4-4 of Figure 2, showing the I/O connector end, or open end of the frame kit;

FIGURE 5 is a transverse, sectional view taken along line 5-5 of Figure 2; FIGURE 6 is a partial, longitudinal sectional view similar to Figure 4, but showing the respective cover members in the assembled condition of Figure 1;

FIGURE 7 is a transverse, sectional view similar to Figure 5, but showing the respective cover members in the assembled condition of Figure 1;

FIGURE 8 is an enlarged, partial sectional view illustrating the preferred cross-sectional shape of the interfitting pin and socket elements along the respective interfacing edge surfaces of the cover members, prior to press fit engagement;

FIGURE 9 is an enlarged, partial sectional view similar to Figure 8, but showing the section through an exemplary press fit pin and socket elements;

FIGURE 10 is a sectional view similar to Figure 4, but showing an alternate embodiment with the use of a pair of hermaphroditic cover members to form the rigid PCMCIA frame kit of this invention;

FIGURE 11 is a sectional view similar to Figure 5, but showing the alternate embodiment of Figure 10; and FIGURE 12 is a partial transverse sectional view showing a complementary groove for receiving a rib to further stabilize the assembly against lateral movement.

Figure 1 illustrates a preferred customized frame kit 10 incorporating the integrity enhancing features of this invention. As more clearly illustrated by the details in the remaining Figures, the frame kit 10 comprises a lower cover member 12 and an upper cover member 14, where such cover members intermate to form the frame kit of Figure 1. Turning first to the lower cover member 12, illustrated as the lower component in Figures 2, 4 and 5, it will be seen that such member comprises a peripheral dielectric frame 16 and a stamped and formed metal shield 18 injection molded to said frame to form the integral cover member 12.

In this preferred embodiment, the metal shield 18 is over only a portion of the frame kit 10, with the balance thereof consisting of a longitudinal extension 20. Whether using a fully shielded or partially shielded frame kit, the dielectric frame 16 defines the peripheral extent of the assembly. The dielectric frame 16, about the periphery, includes a mating surface 22 having plural, spaced-apart circular pins 24, where the diameter thereof has a preset diametrical dimension. Further, disposed along such mating surface 22, between certain adjacent said pins 24, are plural, longitudinally oriented ribs 26, the function of which will be apparent in the discussion later. Finally, as best seen in Figure 5, the metal shield 18 includes an upturned edge 28 within the dielectric frame 16, where the base 30 thereof is exposed outside the frame side 32. As will become apparent in the discussion of the upper cover member 14, it is with this base 30 that continuous shielding between the respective cover members is achieved. The upper cover member 14, depicted as the top component in Figures 4 and 5, is also illustrated in Figure 3, but from the underside thereof to show mating detail. Like the complementary lower cover member 12, the upper cover member 14 comprises a peripheral dielectric frame 40 and a stamped and formed metal shield 42 injection molded to the frame 40 to form the integral cover member 14. In the illustrated embodiment, the metal shield 42 is over a portion of the frame 40, from the I/O connector end 44 to a midpoint or transition area 46. Beyond the transition area 46 is a dielectric extension 48 which is complementary to and matable with the longitudinal extension 20 on the lower cover member 12. Such extensions 20, 48, when fully mated define a cavity therebetween for receiving a portion of the memory card 50 therein, note Figure 3. The upper cover member 14, as best seen in Figure 5, particularly the frame 40, includes along the sides thereof a downwardly extending flange 52 and a lateral mating surface 54. In the injection molding process, the flange 52 is formed within a formed channel 56 of the metal shield 42. With the channel end 60 reversely bent 180°, thereby exposing such end interiorly, a metal- to-metal contact is provided with base 30 of the lower cover member 12 in the assembled condition, see Figure 7.

Opening into the lateral mating surface 54 are plural sockets holes 62, one hole aligned with said upstanding circular pin 24 of the lower cover member 12, note Figure 5. While such pins 24 are circular in configuration, having a preset diametrical dimension, the holes 62 may be characterized as multi-sided in cross-section, where a preferred shape is a hexagon. The enlarged sectional view in Figure 8 illustrates the relationship between a pin 24 and its complementary (hexagonal) hole 62. What appears to be an impossible task to mate same, is quite feasible considering the respective dimensions of the pin and hole, and the use of a plastic or dielectric material that yields or deforms under the application of pressure. A suitable dielectric material for the respective frames is a liquid crystal polymer (LCP) or nylon. Returning again to Figure 8, the pins 24, at the free end thereof are slightly tapered to present a reduced diameter 64 and thereby avoid stubbing on the initial mating of a pin 24 and its corresponding hole 62. The relationship between the pin diameter and reduced diameter of the end is depicted by the concentric dotted lines in Figure 8. The cross-sectional relationship of the pin 24 to its corresponding hole 62 is as follows: where the diameter of the pin is a preset dimension (A) and, the diametrical distance between opposing corners of a pair of adjacent walls of the hole is (B) , then B > A. Further, where the diametrical distance between midpoints of opposing walls is (C) ,- then A > C. By this sizing arrangement, there is sufficient open space within the hole to allow some cooperative displacement or material flow during mating, i.e. press fitting the pin into its corresponding hole. Figure 9 is a sectional view of the mated or press fit arrangement of Figure 8.

An alternate embodiment, while incorporating the unique features of this invention, offers some manufacturing savings, see Figures 10 and 11. In the embodiment of Figure 11, the respective cover members 70, 72 are identical such that a pair may be intermated to form a structurally sound PCMCIA frame kit offering the advantages of this invention. By the provision of a pair of hermaphroditic cover members, only a single, integrated frame and metal shield need be manufactured. In Figure 11, for example, it will be noted that each matable cover member 70, 72, includes a wrap around metal member 74 along one longitudinal side, a mating surface 76, and a plurality of aligned multi-sided holes 78, preferably hexagonal in cross-section, opening into the mating surface. In a complementary manner, the opposite longitudinal side of each cover member 70, 72 includes a dielectric side rail 80 having an edge 82 of the metal shield insert molded therewithin, where a base 82 of the metal shield is exposed for metal-to-metal contact by the opposing or mating cover member, a mating surface 84, and plural, complementary circular pins 86 upstanding from the mating surface 88. It will be understood that the dimensions and preferred shapes and cross-sections of the respective pins and holes are as discussed above relative to the embodiment of Figures 2- 9, and will not be repeated here.

There are two optional features which may be utilized herein to enhance the stability of the assembled frame kit. Along the respective mating surfaces 92,93 of the frame periphery, a rib 26 and complementary groove 94 may be provided, where the rib seats within such groove. By this arrangement, a resistance to lateral movement of one cover member to the other is achieved. As a further stability enhancing feature, one may wish to use sonic welding. Specifically, the pins in the respective holes about the frame kit can be sonic welded utilizing what is called a shear joint. Alternately, as best seen in Figure 12, laterally projecting ribs or protuberances 96 may be incorporated about the frame periphery of one cover member for mating, by snap engagement, with complementary notches 98 located in the other cover member, where localized sonic welding, as known and practiced in the art, can be performed.

Claims

Claims:

1. A PCMCIA frame kit (10) for receiving a planar electronic device for electrical engagement with a complementary device in electronic equipment, said kit comprising a pair of matable, metal cover members (12,14), each said cover member being attached to a dielectric frame (16,40) upon which said planar electronic device is seated, and each said frame includes at least a pair of side rails, characterized in that: said pair of side rails on one cover member include a plurality of upstanding pins (24) , and said corresponding rails on said other cover include a like plurality of multi-sided holes (62) , said pins and said holes being dimensioned so as to prevent torsional twisting of said frame kit.

2. The PCMCIA frame kit of claim 1, characterized in that said pins (24) have a circular cross-section with a predetermined diameter (A) , and said multi-sided holes have a cross-section with a diametrical distance (B) between opposing corners which is slightly greater than said predetermined diameter (A) , and a diametrical distance (C) between opposing said sides which is slightly less than said predetermined diameter (A) , a normal force being applied between said covers to effect a force fit between each respective pin and its multi- sided hole.

3. The PCMCIA frame kit according to claim 1 or 2, wherein said multi-sided configuration is a hexagon.

4. The PCMCIA frame kit according to any preceding claim, wherein one pair of said side rails includes a narrow groove (94) along a mating surface thereof.

5. The PCMCIA frame kit according to claim 4, wherein said side rails of the other cover member include a complementary narrow rib (26) engagable with said corresponding groove.

6. The PCMCIA frame kit according to any preceding claim, wherein said frame kit is generally rectangular in shape, and that said cover members include side rails along three sides, with the fourth side open to expose said planar electronic device for mating with an electrical connector.

7. The PCMCIA frame kit according to claim 5, wherein through the engagement of respective grooves and ribs said engagement offers improved stability to the assembled frame kit.

8. The PCMCIA frame kit according to any preceding claim, wherein the assembled frame kit may be subjected to localized sonic welding to effect a weld between said engaged pin and its respective said hole.

9. The PCMCIA frame kit according to any preceding claim, wherein a free end of each said circular pin is tapered to facilitate entry into a respective said multi-sided hole.

10. The PCMCIA frame kit according to any preceding claim, wherein a plurality of ribs (96) are provided about the side of the peripheral frame of one cover member, and the other cover member includes a like plurality of notches (98) , where a snap engagement of said cover members is achieved through mating of each rib to its respective notch.

11. The PCMCIA frame kit according to claim 10, wherein sonic welding may be applied to each mated rib and notch to further stabilize the assembled frame kit.