US3432794A

US3432794A - Card frame assembly

Info

Publication number: US3432794A
Application number: US575683A
Authority: US
Inventors: John J Churla
Original assignee: Thomas and Betts Corp
Current assignee: ABB Installation Products Inc
Priority date: 1966-08-29
Filing date: 1966-08-29
Publication date: 1969-03-11
Anticipated expiration: 1986-03-11
Also published as: GB1171198A; DE1690286A1

Description

March 11, 1969 .1. J. CHURLA 3,432,794

CARD FRAME ASSEMBLY Filed Aug. 29, 1966 Milli JOHN J. CHURLA A T TOR/VETS.

J. J. CHURLA CARD FRAME ASSEMBLY March 11, 1969 Sheet 2 ors Filed Aug. 29, 1966 T. T W WW INVENTOR. JOHN J. (mun/.4

A 7' TORNE'XF.

March 11, 1969 J. J. CHURLA 3,432,794

INVENTOR. JOHN J CHURLA BY W wW- A 7'7'0RNEY5. l

United States Patent 3,432,794 CARD FRAME ASSEMBLY John J. Churla, Raritan, N.J., assignor to Thomas & Betts forporation, Elizabeth, N.J., a corporation of New ersey Filed Aug. 29, 1966, Ser. No. 575,683 US. Cl. 339-17 Int. Cl. Hk 1/07; H01r 33/76 6 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a new and improved card frame assembly for connector systems, and more particularly to a new and improved card frame assembly for connector systems wherein multiconductor flat cable is terminated to a connector mounted on the card frame.

In a connector system presently in use in electronic devices such as computers, twisted pairs of individual conductors are terminated to one end of a printed circuit board which is mounted on a card frame. The printed circuit board is provided with a plurality of parallel conductor strips which provide conductive connection between the twisted wire pairs and a multiple pin connector mounted on the card frame at the other end of the printed circuit board. Connection is made between an individual conductor and a conductive strip on the printed circuit board by inserting the end of the conductor through a hole in the circuit board and soldering the conductor to the conductor strip. Terminals on the multiple pin connector are also inserted through holes in the circuit board and individual terminals soldered to individual conductor strips on the circuit board. Strain relief of the individual conductors is accomplished by placing a member over the conductors and fastening the member to the card frame.

This connector system has proven disadvantageous for a number of reasons. First, since the individual conductors are not connected directly to the connector pins, but rather to a printed circuit board which acts as a bridge between the connector and the individual wire conductors, thus requiring two connections between conductor and pin, the likelihood of a breakdown in an individual connection is increased. Second, since the connector system comprises a number of separate components, i.e., an individual card frame, individual connector, individual printed circuit board, individual strain relief member and individual conductors, assembly of the system requires a considerable period of time due to the number of individual operations involved. Third, since space is at a premium in present-day computers and other electronic devices, the large amount of space required for a plurality of bunched wire conductors has proven undesirable. Last, the method of strain relieving the individual conductors has not always proven effective since strain relief depends upon the pressure exerted by the strain relief member on the individual conductors and this pressure is not uniform for all the conductors.

The card frame assembly of the present invention obviates the disadvantages encountered in the above-described connector assembly by providing a unitary molded card frame which is adapted to have mounted thereon a multi- 3,432,794 Patented Mar. 11, 1969 ple pin connector and flexible multiconductor cable the conductors of which are terminated directly to the pins of the connector. Means are provided on the card frame to strain relieve cables mounted thereon, to hold the cable to the card frame, to provide for easy removal of the card frame from a card frame holder, to separate individual multiconductor cables to be terminated to a connector mounted on the frame and to allow air flow to the cables.

It is thus an object of the present invention to provide a new and improved card frame assembly which is simple and economical to manufacture.

It is a further object of the present invention to provide a new and improved card frame assembly having a card frame which allows positive termination of conductors of flexible multiconductor cable to a multiple pin connector mounted on the card frame.

It is another object of the present invention to provide a new and improved card frame assembly which may be easily removed from a card frame holder.

It is yet another object of the present invention to provide and new and improved card frame assembly having a card frame which positively strain relieves flexible multiconductor cable.

It is still another object of the present invention to provide a new and improved card frame assembly having a card frame which positively holds down flexible multiconductor cable and which allows air flow to the cable.

Other objects of the present invention will become evident to those skilled in the art from the following description and drawings wherein:

FIG. 1 is a perspective view of a preferred embodiment of the card frame assembly of the present invention;

FIG. 2 is a partially sectional elevational view of the assembly;

FIG. 3 is a top plan view of the card frame of FIG. 1;

FIG. 4 is a sectional elevational view of the assembly of FIG. 1 showing in greater detail termination of the conductors of the flexible cables to the pins of the connector;

FIG. 5 is a sectional elevational view showing alternate termination of the conductors of the cables to the pins of a connector;

FIG. 6 is a plan view of the cables of FIG. 1 showing the ends of the conductors stripped of insulation;

FIG. 7 is an elevational view of the cables of FIG. 6;

FIG. 8 is a partial perspecitve view of the connector of FIG. 1 showing the terminal pins;

FIG. 9 is a modification of the assembly of FIG. 1; and

FIG. 10 is a perspective view of a card frame holder provided with the assembly of FIG. 1.

Referring now to the figures, FIG. 1 shows a perferred embodiment of the card frame assembly of the present invention. As shown, card frame 10 is of unitary construction and is preferably made of insulating material such as plastic or the like. Where card frame 10 is of plastic, it may be formed by molding techniques well known to those skilled in the art. Secured to card frame 10 at one end thereof is a multiple pin connector 12 to which individual conductors of a pair of flexible multiconductor cables are terminated.

Flexible cables

14 and 16 are provided with a plurality of individual conductors 18, the ends of which are terminated by soldering or the like to terminal pins 20 of connector 12.

Card frame 10 is provided with a transverse member 22 which may act as an insulated separator between cables 14 and 16' at the point of termination of conductors 18 to pins 20 of connector 12. This is shown more clearly in FIGURES 2 and 4 wherein member 22 is shown acting as a separator between

cables

14 and 16. Separator member 22 also provides rigidity to frame 10 and the front surface thereof abuts the rear surface of connector 12 to give strength to the assembly.

Cables

14 and 16 are held down to frame by means of fingers 24 which extend inwardly from the sides of card frame 10, cooperating with transverse member 26. A second set of inwardly extending fingers 28 cooperating with transverse member 30 also function to hold

cables

14 and 16 to card frame 10. Hold down is accomplished by

sandwiching cables

14 and 16 between fingers 24 and member 26 and between fingers 28 and member 30. As shown,

cables

14 and 16 are narrower in width at fingers 28 than at fingers 26 and thus fingers 28 are adapted to extend a greater distance from the sides of frame 10 than do fingers 24.

Strain relief and hold down is provided by two sets of inwardly extending fingers 32 in cooperation with transverse bar 34. One set of fingers 32 is disposed on one side of bar 34, while the other set of fingers 32 is disposed on the opposite side of bar 34. As shown in FIGURE 2, the lower surfaces of fingers 32 extend below the upper surface of bar 34, thus causing

cables

14 and 16 to be bent into the shape of a U.

Handles 36 are provided at the rear of card frame 10 to facilitate removal and insertion of card frame 10 into and from a suitable card frame holder to be described hereinafter. Rails 38, provided at the sides of card frame 10, are adapted to slide into suitable channels in a card frame holder.

As shown, pins are staggered in an upper and a lower row and are provided with downwardly extending terminal portions 40, the terminal portions of the pins in the lower row extending farther rearwardly than the terminal portions of the pins in the upper row (see FIG. 8). In order to properly terminate the conductors of

cables

14 and 16 to pins 26, the ends of the conductors of upper cable 14 are caused to extend beyond the ends of the conductors of lower cable 16 (see FIG. 7).

Referring now to FIG. 4, electrical connection between conductors 18 and pins 20 is accomplished by bending downwardly the ends of conductors 18, butting the downwardly bent ends against downwardly extending terminal portions 40 of pins 20 and then soldering conductors 18 to pins 20. As shown in FIG. 4,

cables

14 and 16 are positioned on either side of member 22 which functions both as a support for the cables and as an electrical insulator therebetween. It will be understood that

cables

14 and 16 could also be positioned on the same side of member 22, in which case member 22 would only function as a support. This is shown more clearly in FIG. 5, wherein

cables

14 and 16 are positioned on the bottom of member 22.

Connector 12 is affixed to card frame 10 by suitable fasteners such as rivets 42 which are passed through mounting holes 44 in frame 16 and mounting holes 46 in connector 12.

Cables

14 and 16 are held together by tape 48 or the like at the rear of card frame 10.

The card frame assembly described hereinabove may be adapted to mount electronic components such as resistors, diodes or the like. Thus in FIG. 9, there is shown the assembly of FIG. 1, having resistors 50 connected directly to conductors 18 of cable 14. Connection may be accomplished by any known means such as soldering the leads of resistor 50 to conductor 18.

Referring now to FIG. 10, there is shown a card frame holder (not forming a part of the present invention) adapted to receive the card frame assembly of the present invention. As shown, card frame holder 60 comprises a pair of side members 62 and transverse members 64 affixed to side members 62 by suitable fasteners such as screws 66. Side members 62 are provided with a series of slots 68 to receive suitable card frames such as card frame 10. Rails 38 of frame 10 are adapted to slide within slots 68 for easy insertion and removal thereof. A connector 70 having a plurality of rows of pins 72 is mounted on the front of holder 60, pins 72 having rearwardly projecting portions (not to be inserted into pins 18 of connector 12. Removal of card frame 10 from holder 60 is facilitated by handles 36 which may be gripped by a suitable tool or by hand.

The card frame assembly described hereinabove may be assembled as follows: a suitable multiple-pin connector having exposed terminals projecting rearwardly thereof is afiixed to the end of card frame 10 by fasteners 42. As shown in the drawings, the conductors of a pair of multiconductor fiat cables are stripped of insulation of the ends thereof and soldered to the terminal portions of the multiple-pin connector. The cables may be positioned on opposite sides of separator member 22 (as shown in FIG. 4) or on the same side of member 22 (as shown in FIG. 5

After all of the conductors of

cables

14 and 16 have been soldered to the pins of connector 12,

cables

14 and 16 are bent into a generally U-shape to slip the cables under hold-down fingers 24 and hold-down fingers 28.

Cables

14 and 16 are thus firmly held between fingers 24 and transverse member 26 and between fingers 28 and transverse member 30.

Cables

14 and 16 are then slipped under fingers 32 and bent over bar 34 to complete assembly of the cables to card frame 10.

Cables

14 and 16 are then taped together by a suitable tape 48. Flow of air about

cables

14 and 16 is facilitated by the spaces between transverse members of frame 10.

As shown in FIG. 2, connector 12 is affixed to card frame 10 by fasteners such as rivets 42 or the like. It will be understood that any other suitable type of fastener could also be used such as eyelets, screws, bolts, etc. Although a specific form of connector has been shown and described hereinabove, it will be understood that any type of connector may be used in the assembly of the present invention. It will also be understood that although a pair of cables is shown in the drawings, more or less than two cables could also be used, depending upon the particular application in which the card frame of the present invention is used. Although two sets of hold-down fingers in connection with respective transverse members have been described hereinabove, one set of fingers with a single transverse member may also be used, or more than two sets of fingers with associated transverse members may be used where the length of the card frame necessitates such use.

It will thus be seen that by means of the card frame assembly of the present invention, the disadvantages of the prior art connector assembly have been obviated. Thus, instead of two electrical connections between conductor and connector, in the instant assembly the conductors of the multiconductor cable are connected directly to the connector pins. The bulkiness of a plurality of individual wire pairs is replaced by multiconductor flat cable which takes up much less space. Positive strain relief is provided by integrally molding the strain relief members to the card frame, rather than providing a separate member which must be individually affixed to the prior art card frame. The necessity for expensive circuit boards used as a bridge between the twisted wire pairs and the pins of the connector is obviated by use of multiconductor fiat cable, the conductors of which may be connected directly to the connector pins. Assembly of the conductors to the connector pins is greatly simplified and reliability of the assembly is increased by reducing the number of connections. The connector assembly may be quickly removed from its card frame holder by application of a pulling force on integrally molded handles 36. Cooling of the assembly is accomplished by means of apertures in the card frame between transverse members.

Although a preferred form of a card frame assembly has been described hereinabove and shown in the drawings, it will be understood that other embodiments are within the scope of the present invention, although not specifically described and illustrated herein. Thus, the present invention is not to be limited to this specific ernshown) which are adapted bodiment, but rather the scope thereof should be determined from the following claims.

What is claimed is:

1. A card frame for multiconductor flexible fiat cable comprising a frame, hold-down means on said frame for holding said cable to said frame, said hold-down means comprising a transverse member and first finger means spaced from said transverse member and projecting inwardly from the sides of said frame, strain relief means on said frame for relieving the strain on cable held down to said frame, said strain relief means comprising a transverse bar and second finger means spaced from said bar and projecting inwardly from the sides of said frame, rail means on the sides of said frame for allowing insertion of said card frame into a card frame holder and handle means on said frame at the rear thereof for gripping of said frame.

2. The card frame of claim 1 wherein said first finger means comprises a pair of oppositely disposed fingers spaced from said transverse member and projecting inwardly from the sides thereof and said second finger means comprises a first and a second :pair of oppositely disposed fingers respectively on either side of said transverse bar, said pairs of fingers projecting inwardly from the sides of said frame.

3. The card frame of claim 1 wherein said frame is provided with mounting means for mounting a connector thereon.

4. The card frame of claim 3 including a multiple pin connector mounted on said frame by said mounting means and multiconductor flexible flat cable the conductors of which are electrically connected to the pins of said connector, said cable being held down to said frame by said hold-down means and the strain on said cable being relieved by said strain relief means.

5. The card frame of claim 1 wherein said hold-down means includes a second transverse member spaced from said first transverse member and further finger means spaced from said second transverse member and projecting inwardly from the sides of said frame.

6. The card frame of claim 1 wherein said frame, said hold-down means, said strain relief means, said rail means and said handle means are integrally formed of insulating MARVIN A. CHAMPION, Primary Examiner. PATRICK A. CLIFFORD, Assistant Examiner.

US. Cl. X.R.