US3214723A

US3214723A - Tape cable connector

Info

Publication number: US3214723A
Application number: US114984A
Authority: US
Inventors: Henry P Dupre; Graichen Hans; Robert G Knowles; Rocco J Noschese; Oshva Eugene
Original assignee: Burndy Corp
Current assignee: FCI USA LLC
Priority date: 1961-06-05
Filing date: 1961-06-05
Publication date: 1965-10-26
Anticipated expiration: 1982-10-26
Also published as: BE618452A

Description

Oct. 26, 1965 H. P. DUPRE ETAL. 3,214,723

TAPE CABLE CONNECTOR Filed June 5, 1961 BY/ MKZ United States Patent O 3,214,723 TAPE CABLE CONNECTOR Henry P. Dupre, Wilton, Hans `Graichen and Robert G. Knowles, Norwalk, and Rocco J. Noschese, Rowayton, Conn., and Eugene Oshva, Long Island City, N.Y., assignors to Burndy Corporation, a corporation of New York Filed June 5, 1961, Ser. No. 114,984 1 Claim. (Cl. 339-99) This invention relates to electrical connectors, and more particularly to connectors for flat flexible cable.

A tape or printed cable is essentially a plurality of flat or ribbon like conductors disposed adjacent each other in a common plane and supported by a dielectric. The tapes are manufactured in divers ways; e.g., conductor strips may be disposed between two dielectric sheets and the sheets bonded together; or metal foil may be cemented to a dielectric sheet, the foil milled into strips, and a second dielectric sheet cemented over the foil. Many of these tapes are made of copper ribbons sandwiched between two layers of dielectric such as various forms of polyesters, uorinated polyethylene plastics, polyvinyls, or silicone rubber.

A major problem in the use of flat flexible cables is their connection to electrical equipment or to other flat flexible cables. The conductors are thin, closely spaced, and insulated. The conductors may have a surface lacquer or oxide coat even though they are covered by the dielectric layers, or they may oxidize when the dielectric is removed to prepare a connection. Various methods of attaching connectors to the cables have been proposed. The insulation may be stripped and multicontact connectors soldered or clamped to the cable. Unfortunately, stripping weakens the end of the cable and exposes the conductors to damage; stripping, due to the thinness of the conductors, may `actually nick or cut the conductors;

soldering is inconvenient to accomplish and diflicult to quality control; and clamping is subject to creep.

It is, therefore, an object of this invention to provide a connector having a plurality of contact elements, each of which will make a secure mechanical and electrical connection with a conductor in a flat flexible cable.

It is another object to provide such a connector which may be readily connected to and disconnected from a tape cable.

It is yet another object to provide such a connector which requires no preliminary treatment, such as stripping, of a tlat flexible cable.

A feature of this invention is a connector having a plurality of spaced apart, toothed contacts, each said contact having a plurality of teeth, which are in eifect teeth of uniformly varying length, and which are adapted to penetrate into the tape cable to varying depths and to scrape the included contact, removing any surface coating, and to ake a mechanical and electrical connection therewith.

nese and other objects and features of this invention will"`become more apparent by reference to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective View of a flat flexible cable to fiat flexible cable connection utilizing two identical connectors according to a first embodiment of this invention;

FIG. 2 is an exploded perspective view of the connector of FIG. 1, partially broken away;

FIG. 3 is a detail of FIG. 2 taken along lines 3-3 showing the hermaphrodite contact mating of two connectors according to FIG. 1;

FIG. 4 is a detail of FIG. 2 showing means to align the fiat flexible cable with the connector;

FIG. 5 is a detail of a contact tooth constructed in acice cordance with the invention showing the scraping of the contact teeth into the flat flexible cable.

As may be seen in FIGS. 1, 2, 3 and 4, one embodiment of this invention utilizes a pair of contact blocks which are linked together to obtain a controlled, scraping, penetration ofthe flat flexible cable.

The -connector assembly 9 shown in FIG. 2 comprises an upper contact `block 11 and a lower contact block 13, carrying a plurality of spaced-apart, toothed contacts 15 and 17, respectively. The upper and lower contacts 15 and 17, respectively, are in staggered relation to each other, and the pair of blocks combined have a slight external taper or wedge-shape. The upper and lower contact blocks 11 and 13 are interlocked by a key 19 and keyway 21 to slide towards each other while maintaining their adjacent inner faces 23 and 25 parallel to each other. The upper and lower contact blocks are adapted to be slid into a housing or shell 27 having an inner cavity 29 which symmetrically tapers in height from a larger height at its front, block-receiving opening 31, to a smaller height at its rear, tape-cable-receiving slit 33. The taper of the housing cavity 29 is similar to the external taper of the pair of contact blocks 11 and 13.

It will be seen that when the two interlocked, but slightly spaced-apart, contact blocks 11 and 13 are inserted into the housing, the mating tapers of the housing cavity and the blocks will cam the two blocks towards each other, while the key 19 and keyway 21 will constrain the blocks to maintain their inner faces 23 and 25 in parallel relationship and will also cause a slight relative longitudinal movement between the blocks. Thus, when a at ilexible cable 35 having a plurality of spaced apart conductors 37 disposed within a dielectric 39 is passed through the cable-receiving slit 33 and between the contact blocks, 11 and 13, and the pair of contact blocks are inserted fully into the housing cavity 29, the pair of blocks will be brought together against the at exible cable 35 with a slight relative movement between the blocks.

Each of the contacts 15 and 17 has a plurality of teeth yformed 41 and 43, respectively, therein. These teeth vary .uniformly in size, being shortest at their rear, or housing cable slit 33 proximate end, and longest at their front or housing block receiving opening 31 end. The staggered spacing between the contacts is equal to the spacing between the conductors 37 of the flat flexible cable 35. Thus, for example, the leftmost lower contact is adapted to engage the leftmost tape-cable conductor; the leftmost upper contact is adapted to engage the second from left conductor; and the second -from left lower contact is adapted to engage the third from left conductor. The toothed portions of the lower contacts are also spaced longitudinally from the toothed portions of the upper contacts. This transverse staggering and longitudinal spacingof adjacent upper and lower contact tooth portions provides a maximum air space distance therebetween, to avoid electrical creep or arcing therebetween. The use of teeth of varying length ensures that eaoh tooth will penetrate the tape cable to a slightly different depth. Several teeth will always penetrate the cable insulation to the conductor. Since the depth of tooth penetration becomes progressively deeper towards the front end of the cable, if a tooth does pierce the conductor, even severing it, it will not affect the connection since the rearward teeth have made a proper connection towards the rear of the tlat flexible cable. If desired, the contacts may be made narrower than the conductor, to ensure that piercing 'by a tooth will not sever the conductor. The slight relative longitudinal movement of the contact .blocks ensures that the teeth will scrape the conductors as they pass through the insulation, ensuring a good electrical connection therewith. Individual teeth at 41 and 43 may have the general configuration of a tooth 117 and penetrate a cable 35, as shown in FIGURE 5.

rThe contacts 15 and 17 project out of the contact blocks 11 and 13 and may terminate in any desired configuration for connection to the associated electrical equipment or another connector, The contacts are `here shown to terminate in hermaphrodite ta=bs 45 and 47, respectively, which may be spring-tempered and slightly bowed to engage the mating tabs 51, in a mating connector 53, as shown in FIG. 3.

A gasket 55 may be provided adjacent the cable entry slit 33 between the inside rear end of the housing 27 and the rear ends of t-he contact 'blocks 11 and 13 to seal the rear end of the housing. A contact sealing gasket 57 and a pressure plate 59 may be provided with openings 61 and 63, respectively, to pass the contact tabs 45 and 47 and to seal the front end of the housing 27. I ack screws 65 may .be used between the pressure plate 59 and the housing 27 to force the contact blocks 11 and 13 into the housing cavity 29 to ensure the sealing of the assembly.

If desired, to ensure accurate alignment between the contacts 15, 17 and t-he tape cable conductors 37, pins 67 and 69 may be provided in one contact block 13 to engage locator holes 71 and 73, respectively, punched into the flat flexible cable 35 as shown in FIG. 4.

FIGURE 5 illustrates the manner in which a contact toot-h such as 117 is applied to the surface of a cable 35 at an angle, tending to scrape away the insulation 39 and any coating on the conductor 37, as i-t is driven into the cable.

The individual tooth portions of the contact elements shown in the embodiments illustrated in FIGURES 1 through 4 herein, may each employ the configuration and conductor approach angle of tooth 117, shown in FIG- URE 5. Tooth 117 may be seen to be specifically adapted to penetrate a cable at an angle to the cable surface at the point of contact, so that a slight scraping motion of the teeth parallel to the cable is achieved.

The invention has th-us been described but it is desired to be understood that it is not conned to the particular forms or usages shown and described. The same being merely illustrative, and that the invention may be carried out in other ways without departing from the spirit of the invention and therefore, the right is broadly claimed to employ all equivalent instrumentalities coming within the scope of the appendent claim, and by means of which objects of this invention are attained and new results accomplished, as it is obvious that the particular embodiments herein shown and described are only some of the many that can be employed to obtain these objects and accomplish these results.

We claim:

A connector for a cable including a plurality of insulated cond'uctors disposed in substantially coplanar, parallel, spaced-apart relationship, comprising:

first and second insulating block members constituting a pair dening a mutual interface;

a plurality of spaced-apart contacts mounted in said first block member, each having a plurality of teeth projecting into said interface;

a plurality of spaced-apart contacts mounted in said second block mem-ber, each having teeth projecting into said interface;

means for moving said block members relative to each other along a path forming an acute angle with the plane of said interface, said means comprising a housing member having an inwardly extending cavity for receiving said blocks, a key on one of said block members, and a mating keyway on the other of said block members;

said cavity being of gradually reduced height along the longitudinal axis thereof for urging said Iblocks toward each other as they are longitudinally inserted into said cavity; wherein said key and keyway have their respective mating axes disposed at an acute angle to the longitudinal axis of said cavity, for producing relative motion between said block members in the longitudinal direction to keep said block members parallel as they are being urged together.

References Cited by the Examiner UNITED STATES PATENTS 2,359,541 10/44 Bancroft 339-97 2,929,043 3/60 Phillips 339-99 2,866,170 12/58 Baldridge 339-99 3,070,771 `12/62 Piorunneck 339-174 JOSEPH D. SEERS, Primary Examiner.