IC card closure and welding apparatus

A system is described for completing the construction of an IC (integrated circuit) card, of the type that includes an inner unit (18) formed by a pair of connectors (14, 16) at opposite ends of a circuit board (12), and a sheet metal cover (20) with upper and lower halves (22, 24) that must be fixed together around the inner unit. The system includes front, left, and right weld units (50, 52, 54) arranged about an imaginary rectangular weld region (60), a guide rail (72) extending rearwardly from below the weld region, and a slide assembly (70) with a card-holding fixture, that can slide forwardly into the weld region and rearwardly out of the weld region. A pair of rollers (82, 84) is separately movable forwardly so flanges (86, 88) on the rollers progressively close the upper cover half on the lower one, and then movable rearwardly out of the way, so the slide assembly with a closed card can be moved into the weld region where welds are formed to fix the cover halves together. The system includes a frame (42) with a plate-like platform (44), with the weld units, guide track and slider assembly, and rollers all lying above the platform. A pair of actuators that move the slide assembly and rollers lie below the platform.

BACKGROUND OF THE INVENTION 
IC (integrated circuit) cards are usually constructed in accordance with 
JEIDA and PCMCIA standards, wherein one type of card has a length of 3.370 
inch, a card width of 2.126 inch, and a card thickness of 0.190 inch. Each 
card includes a circuit board with electronic components thereon, a front 
connector and usually also a rear connector mounted at opposite ends of 
the card, and a sheet metal cover that encloses the circuit board and much 
of the connectors. A molded plastic body, or frame, is sometimes used to 
hold the circuit board, connectors, and cover together. A manufacturer of 
parts for an IC card supplies the connectors and sheet metal cover, and 
any body. The customer manufacturers the circuit board to his 
specifications, and must assemble the card components, including fastening 
upper and lower cover halves together. 
A variety of approaches can be used to fasten the cover halves together. 
Apparatus that can rapidly and securely join the cover halves is provided 
by resistance weld equipment. For a relatively small customer, it is 
important that the weld equipment be of relatively small size while 
providing multiple spot welds. It is also highly desirable if the 
equipment can perform and assure full closure of the cover halves prior to 
welding, all in an automated apparatus. 
SUMMARY OF THE INVENTION 
In accordance with one embodiment of the present invention, a method and 
apparatus are provided for completing the assembly of an IC card by 
closing and welding together a pair of sheet metal halves around an inner 
unit formed by a circuit board and a pair of connectors. The apparatus 
includes a frame with a platform having an upper surface and three weld 
units arranged respectively at the front and opposite sides of an 
imaginary rectangular, or parallelepiped, weld region. A guide rail 
extends rearwardly from below the weld region, and supports a slide 
assembly that carries a card having a pair of sheet metal cover halves 
that are to be welded together. A pair of rollers are mounted on holders 
that move forwardly to progressively roll down the upper cover half onto 
the lower cover half, prior to moving the slide assembly with the closed 
covers thereon, into the weld region, where the front and opposite sides 
of the card are welded together. 
A pair of actuators for moving the slide assembly and roller holders 
considerable distances, are located at the underside of the plate-like 
platform. An actuator for moving a pair of ground electrodes up against 
the weld fixture during welding, also lies below the platform. The 
arrangement provides all of the necessary functions in a very compact and 
relatively uncluttered apparatus. 
The novel features of the invention are set forth with particularity in the 
appended claims. The invention will be best understood from the following 
description when read in conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 2 illustrates an IC (integrated circuit) card 10 whose card components 
have been partially assembled. The IC card includes a circuit board 12 
having opposite ends, and front and rear connectors 14, 16 attached to the 
circuit board ends. The board and connectors forming an inner card unit 
18. A sheet metal cover 20 includes upper and lower sheet metal cover 
halves 22, 24. When the covers are closed on one another, upper rails 30 
of the upper cover half lie closely on opposite sides of lower rails 32 of 
the lower cover half. The cover halves of the card of FIG. 2 may be 
connected together by a pair of sheet metal strips 34, 36, so the cover 
can be made of a single piece of stainless steel. It may be noted that 
when the completed IC card 10A of FIG. 1 is used, the front end 38 is 
first inserted into a slot of an electronic device until the front 
connector mates with a connector lying deep in the card-receiving slot of 
the electronic device. 
FIG. 5 illustrates an apparatus 40 which is relatively compact and of 
moderate cost, which can complete the assembly of the IC card, after the 
unit 18 of FIG. 2 has been loaded into the lower cover half 24. The 
apparatus includes a frame 42 with a plate-like platform 44 at the top. 
The apparatus includes three weld units 50, 52, 54 lying about an 
imaginary weld region 60 that is of substantially parallelepiped shape and 
which has a vertical axis 61. That is, the region 60 is of rectangular 
shape as seen in a plan view as well as in side views. The weld region is 
to be occupied by an IC card when it is welded. The first weld unit 50 is 
located at the front of the weld region while the second and third units 
52, 54 are respectively located at the left and right sides at the weld 
region. A slide assembly 70 which can hold the card, can slide along a 
guide rail 72. The guide rail 72 extends from below the weld region 60 in 
a rearward direction R therefrom, to a location rearward of the weld 
region. The slide assembly includes a rigid card-holding fixture 74 with a 
front limiter 76 and with side limiters 78 for closely positioning the 
bottom cover half of the card. A keeper 80 is spring biased forwardly, in 
the direction F, to hold the bottom cover firmly against the front limiter 
76. The apparatus also includes a pair of rollers 82, 84 with roller 
flanges 86, 88 for pivoting the upper cover half to a closed position, 
prior to welding the covers together. 
FIG. 7 shows the partially assembled IC card 10 mounted on the slide 
assembly 70 at a cover closing station 71. It is noted that the rear end 
100 of the card is positioned forwardly, relative to the apparatus arrow 
F. To complete the card assembly, the top and bottom cover halves are 
joined together by moving an upper member (rollers 82, 84) with respect to 
a lower member (the fixture 70 of the slide assembly 70). In particular, a 
pneumatic roller actuator 102 is energized with compressed air to move a 
pair of roller holders 104 in the forward direction F. The roller flanges 
86, 88 roll against opposite sides of the upper cover half 22 to 
progressively move down the upper cover half until it snaps against the 
lower cover half 24. Such progressive lowering of the upper cover half is 
important in assuring proper assembly of the cover halves. As shown in 
FIG. 4, the rails 30 of the upper cover half have inwardly-extending lower 
flanges 110 which lie below horizontal lower cover parts 112. As a result, 
when the upper cover half is moved down into place, it locks in place. The 
provision of welding spots as at 120, prevent the rails 30, 32 of the 
upper and lower cover halves from sliding on one another, which greatly 
increases the rigidity of the cover and therefore of the card. It may be 
noted that applicant may prefer to place each weld 120 so its center line 
122 lies closer to the bottom of the card, where the lower flange 110 
lies, then to the upper end of the card, where the upper corner 124 lies 
which connects a largely horizontal top main cover portion 126 to the 
upper rail 30. This is because the rails are closest together near where 
the lower flange 110 locks to the lower cover part 112, which is part of a 
largely planar lower main cover portion 125. Applicant prefers that the 
weld 120 lie at or below a horizontal center line 128 of the card, so the 
weld is made where the rails lie close together. 
As shown in FIG. 3, the lower rails 32 each forms a lead in 128 near its 
card front end 38. The lead-ins help to deflect the upper rails 30 apart 
as the upper cover half moves down along the lower cover half. It is 
highly desirable to gradually spread apart the upper rails 30 by pivoting 
the upper cover 30 downwardly rather than moving all portions downwardly 
at the same time. Applicant pivots down the upper cover half by means of 
the roller flanges such as 86 shown in FIG. 7. When the IC card 10 is 
placed in the slide assembly 70, applicant first moves the rollers 
forwardly to the position 82F. A roller actuator 102 accomplishes this by 
moving a roller carriage 127 along a roller track 128. Then, a slide 
actuator 130 is energized, which moves the slide assembly 70 forwardly 
until the card 10, with its upper and lower cover halves closed, lies in 
the weld region 60. Another actuator 132 moves a pair of independently 
spring loaded grounding conductors 134 upwardly against the slide assembly 
70 after the slide assembly has moved the card into the weld region. 
Each of the weld units such as 54 includes two weld heads 140, 142. All 
three weld units are identical and each includes two such weld heads. Each 
weld head includes an electrode holder 144 and an electrode 146. Current 
is applied to the electrode holder through an electrical cable 150. As 
shown in FIG. 9, each weld head 140 includes an insulator 152 which is 
mounted within a cylinder 154 that can move within a guideway 158. A 
pneumatic actuator 160 has an actuator piston 162 that can move inwardly, 
in the direction I to move a spring 164 inwardly. The spring moves the 
insulator 152, cylinder 154, holder 144 and the electrode 146 inwardly. 
The actuator can actually move the electrode tip 166 to the position 166A, 
but the card 10 limits the inward movement to the position 166B. After the 
actuator piston has moved inwardly and compressed spring 164, a large 
current such as 600 amperes passes through the cable 150, through a 
terminal 170 at the end of the cable, and through a bolt 172 and a sleeve 
174 to the electrode holder 144 and electrode 146. It is noted that the 
cable 150, terminal 170, and other indicated parts move with the electrode 
holder 144. When the actuator piston 162 moves outwardly again, a retainer 
ring 156 assures that the electrode holder 144 will move outwardly. The 
arrangement of the bolt 170 passing through a lug 176 at the end of the 
terminal 170 into a threaded hole 177 in the holder, provides a compact 
and high current-carrying capacity right-angle connection. 
Each electrode holder 144 includes an aluminum disc with an inward face 178 
and with a central hole 179 for receiving the electrode. As shown in FIG. 
5, each holder has a slit 180, with a screw 182 that can be tightened to 
close the slit to grasp the electrode. The screw 182 can be loosened to 
remove the electrode, so it can be reversed and its opposite end can be 
used. 
As shown in FIG. 7, the long actuators including the roller actuator 102 
slide actuator 130, and the smaller ground actuator 132 are all mounted on 
the plate-shaped platform 44, and all lie below the platform 44, in an 
enclosed space enclosed by the rest of the frame 42. This leaves only the 
slide assembly 70 which must receive the IC card, the rollers such as 82 
which must close the card cover, and the weld units such as 50, 54 which 
must weld the card, lying above the platform. Applicant prefers to use a 
control 190 which controls all of the actuators and the application of 
current. As a result, a worker need only place the card 10 in the position 
shown in FIG. 7 on the slide assembly 70 and depress a pair of safety 
buttons (not shown) to begin and complete the card assembly. As discussed 
above, the rollers such as 82 first move forward and rearward along the 
card to close its cover. The slide assembly 70 then moves forwardly into 
the weld region 60. Each of the weld heads 44 moves sequentially inwardly 
towards the vertical axis 192 of the weld region until the electrode is 
stopped by the card, and welding currents are passed through each of the 
six electrodes. The electrodes are then withdrawn from the card, and the 
rollers 82, 84 and slide assembly 70 are moved rearwardly to their initial 
positions. A worker can then remove the card and place a new card to be 
assembled on the slide assembly. 
Applicant has constructed and successfully tested welding apparatus of the 
construction illustrated, for an IC card having a length of substantially 
3.5 inches, with the other dimensions being proportional as illustrated in 
FIG. 7. Although the invention is shown being used for an IC card wherein 
the upper and lower cover halves are integral, being connected by a pair 
of bendable strips, the apparatus also can be used to complete the 
assembly of IC cards wherein the upper and lower cover halves are separate 
elements. 
Thus, the invention provides apparatus for completing the assembly of an IC 
card. The apparatus includes three weld units lying at the sides of a 
rectangular or parallelepiped-shaped weld region. (An apparatus for 
another IC card uses two of the weld units, arranged at opposite sides of 
the weld region). A guide rail extends from below the weld region in a 
rearward direction and guides a slide assembly which holds an IC card to 
be welded, into the weld region. The apparatus also can include a pair of 
rollers that are mounted to roll against opposite sides of the upper cover 
half to progressively pivot it down against the lower cover half. A roller 
actuator can first move the rollers forwardly to close the card, and 
another actuator then moves the slide assembly forwardly into the weld 
region. Each of the weld units includes at least one weld head that 
comprises an electrode holder that is connected to a cable that has a 
horizontally-extending terminal with a lug, and a bolt extending 
vertically through a hole in the lug and into a threaded hole in the 
electrode holder. The weld units are preferably all mounted on top of a 
plate-shaped platform, with the slide actuator and roller actuator 
preferably lying under the platform. 
Although particular embodiments of the invention have been described and 
illustrated herein, it is recognized that modifications and variations may 
readily occur to those skilled in the art, and consequently, it is 
intended that the claims be interpreted to cover such modifications and 
equivalents.