US3241096A

US3241096A - Current cube tap

Info

Publication number: US3241096A
Application number: US409376A
Authority: US
Inventors: Daniel B Miller
Original assignee: Deutsche ITT Industries GmbH
Current assignee: TDK Micronas GmbH; International Telephone and Telegraph Corp
Priority date: 1964-11-06
Filing date: 1964-11-06
Publication date: 1966-03-15
Anticipated expiration: 1983-03-15

Description

Mmh 15, 3%@ D. B. MILLER 323,96

CURRENT CUBE TAP Filed Nov. 6, 15,164 3 Sheets-Shea?l 2 INVENTORA .QAM/f MILLER ATTORNEY March 15, 1966 D.B.M1LLER CURRENT CUBE TAP 3 Sheets-Sheet 3 Filed Nov. 6, 1964 INVENTOR.

DAN/z 6. M/msf? ATTORNEY United States Patent O 3,241,096 CURRENT CUBE TAP Daniel B. Miller, Providence, RJ., assignor to International Telephone and Telegraph Corporation, Nutley, NJ., a corporation of Maryland Filed Nov. 6, 1964, Ser. No. 409,376 8 Claims. (Cl. 339-157) This invention relates to current taps such as cord connectors convenience outlets and cube taps having male prongs for insertion in a convenience outlet and more particularly to a current tap with a minimum of molding material and contacts of thin `strip material of economical design. The particular design of this invention enables the use of a contact of thin and narrow strip material wherein two strips serve for contacts for a plurality of attachment plugs. In addition the design of the molded insulating body is such that a minimum of molding material is used.

The principal object of this invention is to provide a current tap with a novel contact of thin and narrow strip material, two of the contacts serving to receive the prongs of a plurality of attachment plugs.

Another object o-f this invention is to provide a current tap which is designed for the most economical construction with a minimum of molding material used therein.

Another object of this invention is to provide a current tap with a contiguration that lends itself, in virtue of the fact that the major axes of all female contacts are parallel to conventional molding techniques, such that manual or automatic loading of the mold is simplied, and also the construction of the mold, being more simple, is economical, both vas to construction and maintenance.

A feature of this invention is a current cube tap comprising a molded body of resilient insulating material, the molded body comprising a first pair of parallel plug receivable openings disposed on a tirst side of the body, second and third pairs of parallel plug receivable openings disposed on the side opposite its first side, the second and third pairs of openings being spaced from the axis of the rst pair on both sides of the iirst pair. The body has a recess in the center portion of the body along substantially the length thereof. A pair of parallel contacts are disposed in the insulating body on each side of the recess and in adjacent relationship to the pairs of parallel plug receivable openings, each of the contact strips comprising at one end thereof a U-shaped channel for receiving connector wire, three elongated receptacles with angular ends formed by upper and lower portions of the contact strip which are spread apart to receive the blades of the plug. The upper and lower portions of each end receptacle has an offset tab in the center thereof to form a cooperating tapered arrangement for the plug blade, the upper and lower portions of the center receptacle having offset tabs in the center thereof and disposed in a direction opposite the tabs of the end receptacles, the side of each receptacle opposite each tab having a recess substantially equal to the length and width of the tab from which recess the top is punched and the center receptacle of each contact strip being disposed adjacent the first pair of openings and the end receptacles being disposed adjacent the second and third pair of openings for receiving therein the blades of a plug.

The above-mentioned and other features and objects of this invention will become more apparent by reference to the following description taken in conjunction with the accompanying drawings, in which:

FIGURE 1 is a plan view of the current tap of this invention;

FIGURE 2 is a plan View of the side opposite to that shown in FIGURE 1;

. FIGURE 3 is an end view of the current tap;

FIGURE 4 is a cross section view along line 4 4; FIGURE 5 is a cross section view along line 5 5; FIGURE 6 is a cross section View along line 6 6; FIGURE 7 is another end view of the current tap; FIGURE 8 is an elevation view of one embodiment of the contact strip;

FIGURE 9 is an end view of the contact strip of FIGURE 8;

FIGURE 10 is a plan View of the contact strip of FIGURE 8;

FIGURE 11 is a cross section View along line 11 11;

FIGURE 12 is an elevation view of another embodiment of the contact strip;

FIGURE I3 is an end view of the Contact strip of FIGURE 12;

FIGURE 14 is a plan view of the contact strip of FIGURE 13; and

FIGURE 15 is a cross section view along line 15-15.

With reference to FIGURES 1 through 7 there is shown a current tap of this invention, which comprises a molded body 1 of insulating material. On one side of the molded insulating body which has a substantially rectangular conti-guration, there is shown a pair of parallel openings 3 disposed in approximately the center of the molded body from the end 4 thereof to the point 5 where a taper begins in the body and extends down to the narrow end 6 o-f the plug where the connector wire 7 enters the tap. Each pair of parallel sides at this end are tapered towards the wire end. The parallel openings 3 are disposed apa-rt a sutlicient distance -to receive the blade of a standard commercial attachment plug. On the side 8 which is diametrioally opposite to the side 2 there is shown second and third pairs 9 and 1t), of parallel openings for receiving the blade of a plug attachment which are the same as the parallel openings 3 described above`

Parallel openings

9 and 10 are spaced apart from each other and are on opposite sides of the axis of the parallel openings 3. The

sides

11 and 12 which join the

sides

2 and 8 are slightly curved as are also

sides

2 and 8.

Sides

11 and 12 Iare curved also along the long axis lfrom the end surface 4 and continue beyond the paper start point 5 `and then curve sharply towards the end surface 6 of the tap. As shown in the cross section view of FIGURE 4 the parallel plug openings extend within the tap to a point near the opposite side of the tap to allow for insertion of the 4mating blade plug. Disposed Within the center portion of the body of the tap 1 is a rectangular cavity 15 which extends along the major portion of the body and partially Within the tapered .portion` It will be observed that the wall thickness is substantially uniform for the top and bottom and for the side walls, the wall thickness of the side walls being greater to permit the insertion of the contact strips. The top and bottom walls 16 and 17 can be seen to be thinner than the

side walls

18 and 19. The advantage iered by the cavity is that less molding material is re- [uired .and the uniform wall thickness insures more uniorm and faster cooling. Each of the parallel openings i, 9 and 10 have tapered edges 20 to allow for easy inertion of the blade of the attachment plug. The corilector cord enters the tap at the end 6 and divides into wo channels 21 and 22 which lead to parallel channels b3 and 24 in which are disposed lthe contact strips.

The contact strip will be described with reference to F`IGURES 8 to 11. Two of the contact strips shown in ,hese figures are required for each current tap, one on :ach side of the long axis as shown in FIGURE where :ach contact strip is numbered 25. The contact strip Z5 is linear and comprises substantially an upper portion I6 and .a lower portion 27, both portions, being formed )ut of -the same st-rip material and `both being attached ',ogether at various places where there has been no slitting :hrough for formation of the receptacle portions and the :nd tabs. At one end of the contact strip is a U-shaped :ab 30 which is formed out of one tab element 31 and two :ab elements 32 on the side opposite tab element 31 with :he connecting base section 33. The tab 30 receives one of the connecting wires for Athe current tap and when the wire is properly in position therein

tab elements

31 and 32 are bent over the wire .and securely crimped therein to hold the wire securely in place. Each contact strip Z5 contains 3 receptacles 35 which are in the shape substantially rectangular wi-th angular ends 36, the middle portions 37 of the receptacles being curved inwardly to provide appropriate spring tension and wiping contact on the blades of the attachment plug to be inserted therein. Each end receptacle 35 has 2

tabs

38 and 39. Tab 38 is .approximately in the center of 1the receptacle 35 .and extends from the upper portion 26 of the contact strip. At the top the tab 38 is offset slightly as is shown at 40 to provide a 4tapered entrance as a guide for the blade of the attachment plug. Tab 39 extends upwardly from the lower portion 27 of the contact strip and offset :as shown at 41 so that there is provided with the

cooperating tabs

38 and 39 offset as shown at 40 and 41, an entrance for the blade of the attachment plug which then fits into the receptacle 35 and is securely retained therein by the spring action of the linwardly curved walls 37 of the receptacl-e 35. The same type of tab is :repeated in the opposite end receptacle 35 of the contact strip. Thus there is provided receptacles with offset tabs extending upwardly so that two sets of bla-des can enter from the top goin-g down into the end receptacle through parallel -

openings

9 and 10. The center receptacle 35 has a similar arrangement with inwardly curving walls but here the tabs extend downward from lthe bottom portion 37 and the top portion 26 4as shown at 45 and 46 and are offset in .a similar Imanner to the

tabs

38, 39 to provide a tapered entrance into the receptacle. The center receptacle 35 is disposed to receive the blades `of a plug entering through parallel openings 3. It will be noted that on each portion upper and lower of contact strip 35 there is a recess 50 from which .a

corresponding tab

38, 39, 45 or 46 has been stamped. By virtue of this arrangement also it can be seen that 4the tab element 31 of the U-shaped tabe has been stamped out of the similar recess 51 from the adjoinin-g contact strip. This particular design .as illustrated here provides a novel contact strip on 1A inch centers wher-e no waste of material occurs :and the same contact strip is used to provide receptacles for 3 blades of the attachment plug. Therefore by using 2 of these contact str-ips 25 it is possible to provide .the contact strips for the current cube tap of this invention which can accommodate three `attachment receptacles. In the molding process the contact strips 25 with the connector cord 7 securely crimped in the end tabs 30 are placed in position in the -rnold and molding insulating material is then injection molded about the contact strips and the wire. The preferred insulation `material is polyvinyl chloride, though it is understood that other suitable molding in- .sulating material may be used. The recesses 55 in the contact strips are semi-circular portions of holes punched in the contact strips to facilitate the shearing of'rr of the individual contact strips from the strip sheet which is processed through the punching and shearing machines.

Another embodiment of the contact strip is shown in FIGURES 12-15 inclusive. As in t-he first embodiment of -the contact strip two Iof the contact strips shown in these figures are required for each current tap, one on each side of the long axis as shown in FIGURE 5. The contact strip `66 of the second embodim-ent is linear and comprises three portions, an upper portion, .a middle porti-on 62 and a lower portion 63, :all three portions being formed out of the same strip material and all being attached together at those places, such as 64, where there has been no slitting through for formation of the receptacle portions 65, 66 and `67. At one end of the cont-act strip is the U-shaped tab 30 which is similar to the tab described in connection with the first contact strip and is formed out of one tab element 31 and two tab elements 32 on the side opposite tab element 31 with the connecting base section 33. The three

receptacle portions

65, 66 and 67 are substantially rectangular with angular ends 69, the middle portions 70 of 4the receptacles being curved inwardly to provide appropriate spring tension and wiping contact on the blades of the attachment plug to be inserted therein. Each middle portion 70 and angular portion 69 is curved outwardly as shown a-t 71 to provide a tapered entrance as a guide for the blade of the attachment plug. It will be observed that the outer portions are curved in one direction .and the middl-e portion is curved in the opposite direction. As shown more particularly in FIG- URE 15 the attachment plug blade when inserted will move downward or upward, as the case may be on curved surfaces 71. In this embodiment as in the first embodiirnent, the receptacles vot two contact strips, disposed in lthe .molded body, will .accommodate two sets of Vattachment plug blades entering from one side and one set of attachment plug blades entering from the other side.

While I have described above the principles of my invention in connection with specific apparatus it is to be clearly understood that -this description is ymade only by Way'of example and not as a limitation to the sc-ope of my invention as set forth in the objects thereof and in the accompanying claims.

I claim:

1.. A current cube tap comprising a molded body of resilient insulating material, said molded body cornprising a first pair of parallel plug receivable openings disposed on a first side of said body, second and third pairs of parallel plug receivable openings disposed on the side opposite said first side, said second and third pair of openings being spaced from the axis of said first pair on both sides of said rst pair, a recess in said body along substantially the length thereof, a pair of parallel contact strips disposed in said body, one of said contact strips on each side of said recess and in adjacent relationship to said pairs of parallel plug receivable openings, each said contact strip having formed therein a plurality of longitudinal slits, the slits defining at the sides thereof contact strip portions, said portions further being offset, in opposite directions, with reference to the general plane of the contact strip, and forming therebetween, lateral of said contact strip, a series of at least three receptacles to receive the connector blades of the plug, said receptacles having angular end and side elements formed by said oppositely offset portions, said side elements lying substantially parallel to said general plane save for slight curvature of each toward the said general plane, said side elements each having a plurality of integral guides, one above the other and transverse to the axis of said cube tap, to facilitate reception of the plug blades, the center receptacle of each said contact strip being disposed adjacent said first pair of openings and the end receptacles being disposed adjacent said second and third pair of openings for receiving therein the blades of the plug.

2. A current tap according to claim 1 wherein said recess is a substantially rectangular cavity extending along the long axis of said body and each pair of parallel sides have uniform wall thickness.

3. A current cube tap comprising a molded body of resilient insulating material, said molded body comprising a first pair of parallel plug receivable openings disposed on a first side of said body, second and third pairs of parallel plug receivable openings disposed on the side opposite said first side, said second and third pair of openings being spaced from the axis of said first pair on both sides of said first pair, a recess in said body along substantially the length thereof, a pair of parallel contact strips disposed in said body, one of said contact strips on each side of said recess and in adjacent relationship to said pairs of parallel plug receivable openings, each said contact strip having formed therein a plurality of longitudinal slits, the slits defining at the sides thereof upper and lower portions, said upper and lower portions further being offset in opposite directions, with reference to the general plane of the contact strip, and forming therebetween three receptacles to receive the connector blades of the plug, said receptacles having angular end and side elements formed by said side elements lying substantially parallel to said general plane save for a slight curvature of each toward said general plane, the upper and lower portions of each end receptacle having an offset tab in the center thereof, the upper and lower portions of the center receptacle having an offset tab in the center thereof and disposed in a direction opposite said end receptacle tabs, said center receptacle of each said contact strip being disposed adjacent said first pair of openings and said end receptacles being disposed adjacent said second and third pair of openings for receiving therein the blades of the plug.

4. A current cube tap comprising a molded body of resilient insulating material, said molded body comprising a first pair of parallel plug receivable openings disposed on a first side of said body, second and third pairs of parallel plug receivable openings disposed on the side opposite said first side, said second and third pair of openings being spaced from the axis of said first pair on both sides of said first pair, a recess in said body along substantially the length thereof, a pair of parallel contact strips disposed in said body, one of said contact strips on each side of said recess and in adjacent relationship to said pairs of parallel plug receivable openings, said contact strip having formed therein a plurality of longitudinal slits, the slits defining at the sides thereof upper and lower portions, said upper and lower portions further being offset, in opposite directions, with reference to the general plane of the contact strip, and forming therebetween, lateral of said contact strip, three substantially elongated receptacles to receive the connector blades of the plugs, said receptacles having angular end and side elements formed by said upper and lower portions, said side elements lying substantially parallel to said general plane save for a slight curvature of each toward said general plane, the upper and lower portions of each end receptacle having an offset tab in the center thereof, the upper and lower portions of the center receptacle having an offset tab in the center thereof and disposed in a direction opposite said end receptacle tabs, the side of each receptacle opposite each said tab having a recess substantially equal to the length and width of said tab, said center receptacle of each said contact strip being disposed adjacent said first pair of openings and said end receptacles being disposed adjacent said second and third pair of openings for receiving therein the blades of the plug.

5. A contact strip for a current cube tape having a plurality of longitudinal slits, the slits defining at the sides thereof upper and lower portions, said portions further being offset, in opposite directions, with reference to the general plane of the contact strip, and forming therebetween, lateral of said contact strip, three receptacles to receive the connector blades of an attachment plug, said receptacles having angular end and side elements formed by said oppositely offset upper and lower portions, said side elements lying substantially parallel to said general plane save for a slight curvature of each toward said general plane, the upper and lower portions of each end receptacle having an offset tab in the center thereof, the upper and lower portions of the center receptacle having an offset tab in the center thereof and disposed in a direction oposite said end receptacle tabs.

6. A contact strip for a current cube tap having a plurality of longitudinal slits, the slits defining at the sides thereof upper and lower portions, said upper and lower portions further being offset, in opposite directions, with reference to the general plane of the contact strip, and forming therebetween, lateral of said contact strip, three substantially elongated receptacles to receive the connector blades of an attachment plug, said receptacles having angular end and side elements formed by said oppositely offset upper and lower portions, said side elements lying substantially parallel to said general plane save for a slight curvature of each toward said general plane, the upper and lower portions of each end receptacle each having an offset tab in the center thereof, both said tabs disposed in the same direction, the upper and lower portions of the center receptacle each having an offset tab in the center thereof and disposed in a direction opposite said end receptacle tabs.

7. A current cube tap comprising a molded body of resilient insulating material, said molded body comprising a first pair of parallel plug receivable openings disposed on a first side of said body, second and third pairs of parallel plug receivable openings disposed on the side opposite said first side, said second and third pair of openings being spaced from the axis of said first pair on both sides of said first pair, a recess in said body along substantially the length thereof, a pair of parallel contact strips disposed in said body, one of said contact strips on each side of said recess and in adjacent relationship to said pairs of parallel plug receivable openings, each said contact strip having formed therein a plurality of longitudinal slits, the slits defining at the sides thereof upper, lower, and middle portions, said upper, lower, and middle portions further being offset, in opposite directions, with reference to the general plane of the contact strip, and forming therebetween, lateral of said contact strip, three receptacles to receive the connector blades of the plugs, said receptacles having angular end and side elements formed by said upper, lower, and middle portions, said side elements lying substantially parallel to said general plane, said side elements of said receptacles being curved outwardly to facilitate the entrance of said plug blades and being curved inwardly to exert spring pressure upon said plug blades, the upper and lower portions of each said receptacle being curved in the same direction and the middle portion of said receptacle being spread apart from said upper and lower portions and curved in the opposite direction, said center receptacle of each said contact strip being disposed adjacent said first pair of openings and said end receptacles being disposed adjacent said second and third pair of openings for receiving therein the blades of the plug.

8. A contact strip for a current cube tap having a plurality of longitudinal slits, the slits defining at the sides thereof upper, lower, and middle portions, said upper, lower, and middle portions further being offset, in opposite directions, with reference to the general plane of the contact strip, and forming therebetween, lateral of said contact strip, three receptacles to receive the connector blades of an attachment plug, said receptacles having angular end and side elements formed by said upper, lower, and middle portions, said side elements lying substantially parallel to said general plane save for each having slight curvatures, each being curved outwardly to facilitate the entrance of said plug blades and being curved inwardly to exert spring tension upon said plug blades, the upper and lower portions of each said receptacle being curved in the same direction and the middle portion of said receptacle being spread apart from said upper and lower portions and curved in the opposite direction.

References Cited by the Examiner UNITED STATES PATENTS Parajon 339-21 X Weiss 339-157 Gilbert 339-218 X Boardman 339-22 X Herman et al 339-61 JOSEPH D. SEERS, Primary Examiner. 10 w. DONALD MILLER, Examiner.

Claims

5. A CONTACT STRIP FOR A CURRENT CUBE TAPE HAVING A PLURALITY OF LONGITUDINAL SLITS, THE SLITS DEFINING AT THE SIDES THEREOF UPPER AND LOWER PORTIONS, SAID PORTIONS FURTHER BEING OFFSET, IN OPPOSITE DIRECTIONS, WITH REFERENCE TO THE GENERAL PLANE OF THE CONTACT STRIP, AND FORMING THEREBETWEEN, LATERAL OF CONTACT STRIP, THREE RECEPTACLES TO RECEIVE THE CONNECTOR BLADES OF AN ATTACHMENT PLUG, SAID RE CEPTACLES HAVING ANGULAR END AND SIDE ELEMENTS FORMED BY SAID OPPOSITELY OFFSET UPPER AND LOWER PORTIONS, SAID SIDE ELEMENTS LYING SUBSTANTIALLY PARALLEL TO SAID GENERAL PLANE SAVE FOR A SLIGHT CURVATURE OF EACH TOWARD SAID GENERAL PLANE, THE UPPER AND LOWER PORTIONS OF EACH END RECEPTACLE HAVING AN OFFSET TAB IN THE CENTER THEREOF, THE UPPER AND LOWER PORTIONS OF THE CENTER RECEPTACLE HAVING AN OFFSET TAB IN THE CENTER THEREOF AND DISPOSED IN A DIRECTION OPPOSITE SAID END RECEPTACLE TABS.