US3699499A - Universal electric connector - Google Patents

Abstract

This invention relates to an electric connector comprising two electrically mating bases, called body and cap. The improvement comprises that each base is being made with more than two like, peripherally unevenly spaced cavities for holding contacts, wherein these contacts are all interchangeable brushes within the connector body and all interchangeable prongs within the cap. This allows a three or four cavity connector to be used with a two pole set as well as with a three pole set of contacts, without permitting any mismating of poles as would occur with even spacing. This mating guard may be still improved by a new locking bolt that aligns the bases before mating. After mating the bolt secures the bases against accidental separation. The proposed use of a single type base mold, brush and prong represents the utmost in standardization of parts.

Description

United States Patent Spaderna [5 UNIVERSALELECTRIC CONNECTOR [72] Inventor: Conan H. Spaderna, 404 Farmington Avenue, Hartford, Conn. 06105 [22] Filed: March 8, 1971 [21] Appl. No.: 121,723

[52 US. Cl ..339/91 R, 339/184 M, 339/192 R [51] Int. Cl. ..1 .1101! 13/54 [58] Field of Search ..339/74, 75,38, 40, 42, 91, 339/71, 184, 185, 192, 193; 285/317 [56] References Cited 7 UNITED STATES PATENTS 3,023,394 2/1962 Hubbell ..339/186 2,930,019 3/1960 3,112,973 12/1963 Von Holtz ..339/14 R 2,953,767, 9/1960 Jackson et a1. ..339/92 2,384,267 9/1945 Andersen 123/328 FOREIGN PATENTS ORAPPLICATIONS 119,769 11/1930 Austria ..339/185 648,241 10/1962 Italy ..339/40 [4s] Oct. 17, 1972 96,760 11/1922 Switzerland ..339/185 Primary ExaminerV-Marvin A. Champion Assistant Examiner-Robert A. I-Iafer s71 ABSTRACT This invention relates to an electric connector comprising two electrically mating bases, called body and cap. The improvement comprises that each base is being made with more than two like, peripherally unevenly spaced/cavities for holding contacts, wherein these contacts are all interchangeable brushes within the connector body and all interchangeable prongs within the cap. This allows athree or four'cavity connector to be used with atwo pole set as well as with a three pole set of contacts, without permitting any mismating of poles as would occur with evenspacing. This mating guard may be still improved by a new locking bolt that aligns the bases before mating. After mating the bolt secures the bases against accidental separation. The proposed use of a single type base mold, brush and prong represents the utmost in standardization of parts.

3 Claims, 12 Drawing Figures UNIVERSAL ELECTRIC CONNECTOR In connectors with two mating bases, having more than two cavities in each base, the main feature of this invention is the use of like brushes in the connector body and of like prongs in the cap, however, with uneven peripheral spacing of the cavities. Thus far, uneven peripheral spacing of contacts in connectors was not deemed sufficient precaution against inserting prongs into slots of the connector body not intended for them. Therefore not matching contacts were made of a different size. Also, slots of different size had to be provided for their passing through. All configurations with peripherally arranged contacts, proposed by the National Electrical Manufacturers Association, such astho'se in publication No. WD 1968, show contacts of many radii, and different sizes on the same radius; further there is an unattractive radial contact addition, called a dog foot, in every connector with more than two cavities. All this can hardly be considered top economy. To avoid such dog feet, according to this invention, means to reduce the outside diameter of the connector, while keeping the same safe distance between contact and perimeter. Special tooling is not needed for contacts of like peripheral size.

Forced mismating of the polarities can be further forestalled by mate means, such as center pin and bushing, differently made and used for various volt and ampere ratings or for equipment grounding and system grounding. Plugging becomes impossible if mate pin butts against mate pin or bushing against bushing or by narrower borings, barring wider pins. Besides being mate guards, the mate means may serve for conventional grounding; yet, their molded cavity may be the same for many such means.

Another feature of the invention is alocking bolt that aligns the connectorbases for mating and secures them against accidental separation, caused by shocks in car or plane. The bolt is seated in a through hole near the perimeter of one base and fits into lengthwise key grooves of the other base and of two terminal covers. If there are no terminal covers, the locking bolt may be made shorter by the length of both covers. Perpendicular arms of the bolt may be turned over the outermost faces of the connector and fall into catches, provided there.

The invention is shown in the drawing but not limited to drawn details.

In the drawing:

FIG. 1 is a front view of a connector body;

FIG. 2 is a side view of a section thereof on line A- A through FIG. 1, looking from the right of FIG. 1, with a terminal cover;

FIG. 3 is an end view of the terminal cover in FIG. 2, looking from the right of FIG. 2;

FIG. 4 is a front view of a connector cap;

FIG. 5 is a side view thereof in a section on line B B through FIG. 4, seen from the right of FIG. 4;

FIG. 6 is an end view thereof, seen from the right of FIG. 5;

FIG. 7 is a front view of a connector body together with a shell box;

FIG. 8 is a side view of a section thereof on line C C through FIG. 7, looking from the right of FIG. 7;

FIG. 9 is a side view of a mate pin, able to mate with the bushing above;

FIG. 10 is a side view of the whole connector assembly with a locking bolt in open position; and

FIG. 11 is a side view of a locking bolt end with a spring-loaded knob rod, housed :in a handle.

FIG. 12 is a view of the latch device of the connector.

In FIG. 1 the plastic housing 3 of a connector body 1 has a central cavity, filled by a grounding mate bushing 2, further two counter-sunk openings 4 with through holes 5 for two screws 6, screwing into a terminal cover 7, see FIG. 2. Shown by dashed lines in FIG. ,1, cavities 8 under the mating wall 9 house brushes 10 with a terminal binding screw 11. The cavities 8 and the brushes in them can be entered through peripherally arrayed slots12. These slots are made for straight and round prong blades. Blanks from brass, bronze or copper band are press formed into brushes and prongs. The blades 31 in FIG. 4 have straight mating faces. If the slots 12 are molded for the round blade of FIG. I, then slots and brush entrances follow the outlines of the blade. Electric barriers 14 between the cavities 8 prevent flashovers. The brass mate means is here a bushing 15. One finds out by relative rotation of the bases that prong blades and body slots match in only one position, that of FIGS. 1 and 4. Other means have to guard against mating of bases for different voltage or current rating.

One such means is a stepped bore in the mate bushing. The step 16 may vary in depth to distinguish the various electric ratings and ground from non-ground ing. This step 16 has to match with that of mate pin 17 in FIG. 5, to allow the cap 21 to mate with the body 1.

The bushing 15 has a binding screw for a ground wire. The two mate means have the same hexagonal middle part 19, which, seated in a recess 19', holds back the mate means from riding up in direction of the terminal cover 7. A matemeans cannot ride out the opposite way, as it sticks through the center hole of a wiring pan 20 and is riveted to the inside of the pan by an eyelet rivet 20'.

The plastic terminal cover 7 of FIGS. 2 and 3 admits through an opening 22 a cord 47, see FIG. 10. An electrician ties down the cord wires under the proper binding screws. Then he attaches the terminal cover to the body housing 3 by screws 6 and'tightens the grips 23 by screws 24,making the screws slide toward each other until they take a firm hold around the cord. New in cover 7 is the locking bolt25 with locking arms 26; the bolt is held captive in a lengthwise through hole 28 of the body 1. While connector body and cap mate with their covers attached, the locking bolt enters a lengthwise key groove 27 of cap and cover. In FIG. 10, the locking bolt 25 is then pushed until its locking arms 26 on either end can be turned from their open position 26 to the closed position 26, see FIG. 3. To the locking arms may be added convenient handles 29 and little knobs 30, as seen in FIG. 11, that fall into matching catches 46 on the cover surface when the connector is locked. After unlocking the bases are pulled apart by the cords 47 in direction of the arrows in FIG. 6; no twist is necessary. Straight separation is always easier, even if some damage had been done to the contacts by long service. Twist lock connectors need here a twist and a straight pull, which requires a much clearer path for the prongs between the brushes.

The connector cap 21 is drawn in FIGS. 4, 5 and 6. In recesses of the plastic housing 36, bushings 38 with hexagonal bottom and cylindrical top have a threaded top hole. By an eyelet rivet each bushing is fastened to a flat, pierced prong base 37 The latter sits deeply in the housing terminal side, to avoid short circuits. Into the threaded top holes screw binding screws 11.

The mate pin 17 of FIG. 5 has a step with diameters that are above and below the diameter of an ordinary mate pin 17, seen in FIG. 9. This bars the mate pin from entering fully into the ordinary mate bushing of FIG. 8. The mating of pin 17 with bushing 15 stops midway, too, as beyond step 16 the channel is too narrow for pin 17'. In both cases the prongs do not even reach the bushes. Moreover, the step 16 could be laid out for lesser depths than shown, to further tell apart connectors of divergent rating. The mate means in body and cap may be transposed to mark different amperage at the same voltage. Doing no harm, the butting of identical mate means will warn against inadequate fuse protection for the load connected.

A shell box 32 of soft drawing brass is outlined in 7 FIGS. 5,7 and 8 with pierced earlobe-type lugs 33 extending from the shell lift 34 radially towards the shell center. These lugs need matching places 35 on the mating side of a cap and on the terminal side of a body to rest on. These places, chosen to make the two shells alike, can be molded in by an exchangeable molding insert. Dash-dot lines mark the lugs 33 and the rivets 39 that fasten the shell 32 to the cap housing 36, using counter sink 4' on the terminal side. Thus, an inlet or receptacle with prongs is formed in which a connector body can mate.

A ground connection between mate means and metal equipment can be made as shown in FIG. 6. A lead strip 40 is at one end pressed under the wiring pan 20, at the other end held in a counter sunk hole 4' under a rivet head, which connects through its rivet 39 with shell 32 that is tied down to the equipment metal.

In FIGS. 7 and 8 the connector body 1 of FIGS. 1 and 2 has been converted into a two pole body 1', usable as a wall receptacle. After removing a molding insert, a lid 41 can be molded on, closing the third cavity, as shown by dashdot lines in FIG. 7. The same may be done to the cap and, if there is no grounding, to the central cavities. A shell box 32 is'seen here with mounting lugs 42 apart by 180. Yet, experience has borne out that screws or rivets, spread at any angle over 120 are sufficient for the support of housing or cover. In FIG. 2, where no shell is needed, the gap of the rest place 33 is filled by a fiber washer 43 of the screw 6.

In FIG. 11 an end of the locking bolt 25 contains a spring loaded knob rod 44, seated in a handle 29. A spring 45 assures pressing of the knob 30 into a catch 46 in the end face of the connector until the locking arm 26 is turned away from the catch. If the cords 47 are clamped down on the equipment and no covers are desired, a shorter locking bolt may lock only body and cap together, with the lockingarms swivelling over the outermost end faces of connector body and cap after their mating. The knobs will fall into catches 46 there, as shown in FIGS. 1 and 4 in dotted lines and in FIG. 11. r

If made from a high impact plastic, the housings of the bases could be provided'at their mating ends with the locking device of FIG. 12. One base has a plastic snapon prong 48 with a knob 49, the opposite base has a matching catch 50 with a catch hole 51 molded into the rim 52.

I claim: 1. A universal electric connector, comprising a cap base and a body base, each of which is formed with at least two cavities, one set of prong contacts with their terminals housed in the corresponding cavities of the cap base and one set of brush contacts with their terminals housed in the corresponding cavities of the body base, the bases having on their cooperating end faces entrance slots which extend to the cavities, said slots arranged on a peripheral circle of each of said faces at such unequal spacings That said bases are polarized with respect to each other, to allow mating of said contacts' in one position only, a mating pin attached to one base and a cooperating bushing recessed in the other base to reinforce the polarized connector structure, and a locking bolt having at each end a means for pivoting said bolt and a latch means, said bolt being attached to one of said bases by being housed in a through hole parallel to the connector axis, the other said base being formed with an open key groove for insertion of a part length,of the bolt, and latch means on the outer end faces of the bases to cooperate with the latch means on said bolt.

2. Connector as set forth in claim 1, in which the latch means is a spring loaded rod guided in said handle of the locking bolt and bearing a knob that sticks out at the end of this handle to cooperate with a catch formed in the nonmating end face of the connector.

3. Connector as set forth in claim 1, in which the bases are shaped with a shouldered recess penetrating them; the mate means pin. and bushing formed with a thin prolongation are received by the shouldered recess from the mating base end and protrude beyond the recess where they are fastened to a terminal; and bushing and pin are stepped at different depth for a different voltage rating.

Claims (3)

1. A universal electric connector, comprising a cap base and a body base, each of which is formed with at least two cavities, one set of prong contacts with their terminals housed in the corresponding caviTies of the cap base and one set of brush contacts with their terminals housed in the corresponding cavities of the body base, the bases having on their cooperating end faces entrance slots which extend to the cavities, said slots arranged on a peripheral circle of each of said faces at such unequal spacings That said bases are polarized with respect to each other, to allow mating of said contacts in one position only, a mating pin attached to one base and a cooperating bushing recessed in the other base to reinforce the polarized connector structure, and a locking bolt having at each end a means for pivoting said bolt and a latch means, said bolt being attached to one of said bases by being housed in a through hole parallel to the connector axis, the other said base being formed with an open key groove for insertion of a part length of the bolt, and latch means on the outer end faces of the bases to cooperate with the latch means on said bolt.

2. Connector as set forth in claim 1, in which the latch means is a spring loaded rod guided in said handle of the locking bolt and bearing a knob that sticks out at the end of this handle to cooperate with a catch formed in the non- mating end face of the connector.

3. Connector as set forth in claim 1, in which the bases are shaped with a shouldered recess penetrating them; the mate means pin and bushing formed with a thin prolongation are received by the shouldered recess from the mating base end and protrude beyond the recess where they are fastened to a terminal; and bushing and pin are stepped at different depth for a different voltage rating.

Images