US3605059A

US3605059A - Back-wired electrical connector device

Info

Publication number: US3605059A
Application number: US786698A
Authority: US
Inventors: Vincent F Lipinski; George A Riley
Original assignee: Harvey Hubbell Inc
Current assignee: Hubbell Inc
Priority date: 1968-12-24
Filing date: 1968-12-24
Publication date: 1971-09-14
Anticipated expiration: 1988-09-14

Abstract

This disclosure relates to an electrical connector device having terminal-contact members with terminal portions retained in cavities in an insulator body, each terminal portion having binding plates angularly disposed with respect to the axis of the device. Angularly disposed wire entry openings are provided in the insulator body to direct wire lead ends to the binding plate wiring areas. The terminal-contact members and the insulator body are formed with keying means to provide noninterchangeability of these members in the cavities, and a protective cover is secured to the insulator body with a labyrinthian seal located between the insulator body and the protective cover to protect the wiring areas from foreign matter.

Description

United States Patent [72] Inventors Vincent F. Lipinski 3,461,417 8/1969 Schumacher et a1. 339/14 P Smfiord; FOREIGN PATENTS [2 App] No 22%; 635,745 1/1962 Canada 339 14 P 1 22] Filed Dec. 24,1968 438,614 12/1926 Germany 339/ 05 [45] Patented Sept. 14, 1971 Primary ExaminerEmest R. Purser [73] Assignee Harvey Hubbell, Incorporated Assistant ExaminerTerrell P. Lewis Bridgeport, Conn. Att0meyWooster, Davis & Cifelli [54] BACK-WIRED ELECTRICAL CONNECTOR DEVICE ABSTRACT: This disclosure relates to an electrical connector 3 Claims, 8 Drawmg Flgs.

device havmg termlnai-contact members w1th termmal por- [52] US. Cl 339/14 L, tions retained in cavities in an insulator body each terminal 339/105, 339/191 339/192 339/195 portion having binding plates angularly disposed with respect 339/196 R1 339/263 R to the axis of the device. Angularly disposed wire entry [5 l Int. Cl Holt 3/06, openings are provided in the insulator body to direct wire lead H011 33/72 ends to the binding plate wiring areas. The terminal-contact [50] Field of Search 339/14, members and the insulator body are formed with keying 105, 191, 192, 195, I96, 263 means to provide noninterchangeability of these members in 56 R I CM the cavities, and a protective cover is secured to the insulator I 1 e I body with a labyrinthian seal located between the insulator UNITED STATES PATENTS body and the protective cover to protect the wiring areas from 3,030,605 4/1962 Carissimi 339/263 X foreign matter.

1 o/ x r.- o :1 e

PAIENIED E $605059 SHEET 2 BF INVENTORS'.

BACK-WIRED ELECTRICAL CONNECTOR DEVICE BACKGROUND OF THE INVENTION Thi invention relates to back-wired electrical connector devices, and more particularly to safety and wiring condition improvements in these devices.

In conventional back-wired connector devices the terminal binding plates of the terminal-contact members and their aligned wire entry openings formed in the insulator body are parallel to and are disposed around the axis of the device. The wire lead ends extending from the cable are not aligned with the wire entry openings and must be dogleg bent in order to be introduced to the wiring area. Thus, back wiring the device is a time-consuming operation.

Often the grounding terminal-contact member and the line terminal-contact members of the usual connector devices are interchangeable. Assemblers are relied upon to place the correct terminal in the correct pocket of the device. Human error may result in a faulty device, i.e. one which might lead to a serious accident. Thus, it would be highly desirable to provide an electrical connector device in which the terminal-contact members are not interchangeable and in particular one in which the line members are not interchangeable with the grounding member.

Furthermore, the usual electrical connector devices of this type generally include protective covers which are secured to the usual insulator body to protect the wiring area. The cover is joined with the insulator body in such a way as to leave a straight-line path from the exterior of the device to the wiring area. This straight-line path may permit conductive dust, wire strands, and other foreign matter to form a conductive path from the interior current carrying parts to the outer surface of the device, thus creating a hazardous condition. Also, high potential failure frequently occurs between the terminal members because they are not sufficiently isolated from one another within the insulator body.

SUMMARY OF THE INVENTION Accordingly, it is the primary object of this invention to provide a back-wired electrical connector device in which the insulator body is designed to present its wire entry openings and terminal binding plates at an angle to the axis of the device and to the axis of the cable to permit lead end wire entry at a natural and convenient angle.

Another object of this invention is to provide chambers in the insulator body to insure that the metal terminal-contact members are isolated from one another and to provide keying means on the terminal members and in the chambers to prevent interchangeability between the grounding and line terminal members.

Yet another object of this invention is to provide an electrical connector device having an improved labyrinthian seal between the protective cover and the insulator body to hinder entry of foreign matter into the wiring area.

A still further object of this invention is to provide a wire lead end-clamping arrangement which provides clearance for larger wires and better contact between the wire and the terminal binding plate.

To accomplish several of these objects, in one form a backwired electrical connector device is provided which comprises an insulator body within which is retained the terminal portions of several terminal-contact members, each terminal portion being isolated from every other terminal portion. Each terminal portion includes axially extending mounting means, a binding plate which is angularly disposed with respect to the axis of the device and carries a terminal clamping screw therein and a clamping nut threadedly engaged with the screw shank. A wiring area is defined by radial openings formed in the insulator body to provide access to the terminal clamping screws, and wire entry openings formed in the insulator body to provide access to the binding plates, the axis of these wire entry openings being angularly disposed with respect to the axis of the device and substantially parallel to the plane of the binding plates. A protective cover is mounted over one end of the insulator body to enclose the wiring area and labyrinthian sealing means is located between the insulator body and the protective cover to hinder entry of foreign matter into the interior of the device.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and further details of that which is believed to be novel and the invention herein will be clear from the following description and claims taken with the accompanying drawings wherein:

FIG. I is a side elevational view of a disconnected electrical connector constructed in accordance with this invention;

FIG. 2 is a view of a connected electrical connector partially broken away to show the interior of each connector device;

FIG. 3 is a sectional view taken substantially along line 3-3 of FIG. 2;

FIG. 4 is a sectional view showing the manner in which the grounding female terminal-contact member is mounted in the connector device;

FIG. 5 is a sectional view taken substantially along line 5-5 of FIG. 2;

FIG. 6 is a sectional view taken substantially along line 6-6 of FIG. 2;

FIG. 7 is an exploded perspective view showing the male and female line terminal-contact members; and

FIG. 8 is an exploded perspective view showing the male and female grounding terminal-contact members.

DESCRIPTION OF THE PREFERRED EMBODIMENT Turning now to the drawings, there is illustrated in FIG. I an electrical connector 10 including a connector cap 12 and a connector body 14. Each connector device includes an insulator body 16 of different construction to which the subscript b or c is added to indicate the connector body or the connector cap. A protective cover I8 similarly constructed in both devices is secured to the insulator body and encloses a wiring area located at the enclosed end of the insulator body 16. Electrical power cables C enter each of the connector devices and are strain relieved by means of cable clamps 20 which may be selectively moved toward clamp portions 22 of the protective cover 18 by means of a clamping screws 24. The construction of the protective cover 18 and the cable clamps 20 is fully described in the copending patent application entitled Plastic Cable Clamp, Ser. No. 781,846 filed Dec. 6, 1968, which is assigned to the same assignee as the instant application.

The connector cap I2 comprises the insulator body which is made of two plastic parts, viz a terminal retainer 26 and a contact holder 28 which are secured together by means of a rivet 30 embedded in the contact holder. The rivet passes through a center post 32 located on the contact holder 28 which enters a positioning recess 34 in the terminal retainer 26. In practice, a drivescrew may be used in lieu of a rivet.

The plastic terminal retainer includes circumferentially spaced molded-in chambers 36 to receive portions of terminal-

contact members

74 and 76. These chambers 36, illustrated in FIGS. 2, 3 and 5 each include a pair of sidewalls 38, an end wall 40, a top wall 42 and an open wall 44 opposite the end wall 40. Opposed axially extending grooves 46 are formed in the sidewalls, a groove 48 is formed in the top wall 42, and a captivating seat 50 is formed about a portion of the open wall 44 for assisting in back wiring the device. The opposed grooves 46 define a positioning slot in each of the chambers 36. One of the positioning slots thus formed is intended to receive grounding terminal-contact member 74 and in wider than the other two. An axially and radially inwardly extending groove 52 formed in the end wall 30 opens to the center post 32 at one end. A wire entry opening 54 passes through the top wall 42 and is angularly disposed with respect to the axis of the device. Slots 56 are provided in the periphery of the terminal retainer 26 to pass securing screws IMP.

The contact holder 28 (note FIGS. 2 and 6) is a generally cup-shaped member including a planar base 58 having arcuate slots therein for passage of portions of the terminal-

contact members

74 and 76. Two of the slots 60 are described on the same circle and are intended to pass line terminal-contact elements and the third slot 62, described upon a smaller circle is intended to pass the grounding terminal-contact member. The base 58 has an annular lip 64 extending in the same direction as the center post 32 surrounded by an annular rim 66. Circumferentially spaced recesses 68 are provided in the face of the planar base 58 from which the center post 32 extends. Axial openings 70 with counterbores 72 are provided in the contact holder. When the terminal retainer 26 and the contact holder 28 are secured together the annular lip 64 encircles a portion of the terminal retainer, the recesses 68 are in alignment with the chambers 36 and the openings 70 are aligned with slots 56 for passage of elongated securing screws 110.

The electrical connector illustrated is a three-wire device and includes two line terminal-contact members 74 and a grounding terminal-contact member 76. The male grounding terminal-contact member 76 is shown mounted in the insulator body 160 of the connector cap 12 in FIG. 2, and is shown in detail in FIG. 8 and the line terminal-contact member 74 is shown in detail in FIG. 7. The mail grounding and line members shall be described with the same reference numerals where applicable. Each member includes a terminal portion 78 and a contact blade 80 connected by means of an integral dogleg portion 82. The terminal portion is provided with axially extending lanced mounting wings 84 which are received in the axial grooves 46 and a binding plate 86 which is angularly bent with respect to the axis of the device, its end 88 being captured in the groove 48. A plain opening 90 is formed in the binding plate 86 for passage of a usual back-wiring-type clamping screw 92 having a flange 94 surrounding its head 96. The flange 94 is captured in the captivating seat 50 of the terminal retainer 26 and restrains the clamping screw 92 against shank axial movement when the screw is rotated. A clamping nut 98 is threadedly engaged on the shank of the screw, its tapped opening 100 being eccentrically located so as to provide a greater wire-capturing land on one side of the opening 100 than on the other. As the clamping screw 92 is rotated, the clamping nut 98 will move along the screwshank in the usual manner. The groove 52 has been provided to clear the end of the clamping screw 92 without enlarging the entire chamber 36, since an enlarged chamber might result in high potential failure between the terminal-contact members due to poorer isolation of the members.

The grounding member 76 differs in construction from the line member 74 so as to prevent interchangeability of these members as wiil be discussed hereinafter. Therefore, the lanced mounting wings 84 of the grounding member are wider set than the wings of the line member, the dogleg portion 82 is longer on the grounding member and a key 102 is formed at the end of a differently shaped contact blade 80.

The protective cover 18 is secured to the insulator body to protect the wiring area 104 in which wire lead ends W are introduced through wire entry openings 54 to the binding plates 86. The cover is substantially cylindrical in shape its sidewall 106 passing over and lying in close proximity to the annular lip 64 and its edge 108 abutting the annular rim 66. This engagement forms an annular labyrinthian seal between the insulator body and the protective cover. The protective cover 18 is secured to the insulator body by means of several elongated securing screws 110 which pass through openings 70 and slots 56 and are threadedly engaged in tapped openings 112 formed in formations 114 located on the interior wall of the cover.

The connector body 14 clearly shown in FIG. 2 includes an insulator body 16b also formed of two parts, one of which is a terminal retainer 116 which is of the same shape as the terminal retainer 26. The contact holder 118, however, is generally cylindrical element having a central axial core 120 in which an elongated rivet 122 is embedded to secure the terminal retainer 116 and the contact holder 118 together. Elongated circumferentially spaced chambers 124 are provided to house the female terminal-contact members and 132. The contact holder 118 is also provided with an annular lip 126 surrounded by an annular rim 128 to form the unique labyrinthian seal between the protective cover 18 and the insulator body 16b.

The female terminal-contact members include line members 130 and a grounding member 132. Those elements of the female terminal-contact members which are similar to their male counterparts are illustrated in the drawing with the same numerals to which a prime has been added. They are secured in the terminal retainer 116 in the same manner as described above with respect to the connector cap. The contact portion of the female members 130 and 132 is in the form of the usual contact spring assembly and keying means is provided to ensure that a line spring assembly 134 cannot be placed into the elongated chamber 124 intended for the grounding spring assembly 136. The keying means includes a pair of aligned laterally outwardly extending feet 138 on the line spring assembly 134 which cooperate with receiving seats formed in the chamber (not shown) and a pair of offset laterally outwardly extending feet 140 on the grounding spring assembly 136 which cooperate with receiving seats 142 formed in the grounding spring elongated chamber 124 (note FIG. 4).

It should be apparent that the objects of this invention have been achieved by the unique construction of the above described back-wired connector devices. Wiring of the devices has been simplified by means of the novel angularly disposed wire entry openings 54 and the substantially parallel angularly bent binding plates 86 which permit entry of the wire lead ends W at a natural and convenient angle.

The

terminal retainers

26 and 116 which are identical in the connector cap device 12 and the connector body device 14 are constructed with pairs of mounting-wingreceiving grooves 46 defining positioning slots to receive the lanced mounting wings 84 of the terminal-contact members. One of the positioning slots is wider than the other two and receives the wider mounting wings of the grounding terminal member. However, if an assembler should accidentally insert a smaller line terminal member into the grounding-positioning slot, he would not be able to assemble the contact holder to the terminal retainer since the dogleg portion 82 of the line terminalcontact element 74 is shorter than the dogleg portion of the grounding terminal-contact element 76. With respect to the mounting of the spring assemblies, it should be noted that the foot configuration of these members will prevent the line members from being inserted into the grounding spring chamber 124. In this manner, noninterchangeability of the metal current-carrying parts of the device has been ensured, resulting in a safer device.

Wiring of this unique device is further simplified by means of the novel clamping nut 98 formed with the eccentric tapped opening 100 which provided better wire-binding plate contact and more clearance for larger wires. The clamping screw 92 passing substantially tangent to the wire entry opening 54 also provides greater wire clearance and eliminates bending of the wire lead end around the screwshank which exists in prior art devices.

Having described this invention of an improved electrical connector device, it will be readily appreciated by those skilled in this art that a connector device embodying this invention provides improved safety by means of the isolation of the metal parts from one another, the improved labyrinthian seal formed between the protective cover and the insulator body, and the noninterchangeability of current-carrying metal pans. Furthermore, back wiring of these devices is simplified by means of the natural angle of wire lead end entry into the wiring area of the device and the novel construction of the clamping nut 98.

it should be understood that the present disclosure has been made only by way of example and that numerous changes in details of construction and the combination and arrangement of parts may be resorted to without departing from the true spirit and the scope of the invention.

What is Claimed is:

l. A back-wired electrical connector body comprising: an insulator body including a terminal retainer element and a contact holder element secured thereto, said contact holder element having spring contact receiving chambers; plural terminal-contact members carried by said insulator body; each of said members having a terminal portion disposed in said insulator body and isolated from every other of said terminal portions; each of said terminal portions including axially extending mounting means and a binding plate which is angularly disposed with respect to said mounting means and the axis of the device; one of said terminal-contact members being a grounding member having contact portions and the others being line members having spring contact portions; said grounding member having keying means in the form of wider mounting means than said line terminal mounting means; said terminal retainer element including means to receive said wider mounting means; each of said members including keying feet extending laterally outwardly from the spring contact portions thereof, the keying feet located on said line members being aligned and the keying feet located on said grounding member being offset with respect to one another; one of said spring contact receiving chambers being a grounding contact receiving chamber and the others being line contact receiving chambers, said chambers including seats for receiving the respective keying feet so that the grounding spring contact portions may not be seated in any of said line contact receiving chambers and the line spring contact portions cannot be seated in said grounding contact receiving chamber; terminal clamping screws rotatably carried by said binding plates; clamping nuts threadedly engaged with said screws and nonrotatably mounted in said insulator body; radial openings formed in said insulator body to provide access to the heads of said terminal clamping screws; wire entry openings formed in said insulator body providing access for wire lead ends to said binding plates, the axes of said wire entry openings being angularly disposed with respect to the axis of the device; and a protective cover secured to said insulator body to enclose said terminal portions.

2. a back-wired electrical connector device comprising: an insulator body; plural terminal-contact members carried by said insulator body; each of said members having a terminal portion disposed in said insulator body and isolated from every other of said terminal portions; each of said terminal portions including axially extending mounting means and a binding plate which is angularly disposed with respect to said mounting means and the axis of the device; terminal clamping screws rotatably carried by said binding plates; clamping nuts threadedly engaged with said screws and nonrotatably mounted in said insulator body; each of said clamping screws being eccentrically mounted in its associated clamping nut so as to provide a larger wiring land; radial openings formed in said insulator body to provide access to the heads of said terminal clamping screws; wire entry openings formed in said insulator body providing access for wire lead ends to said binding plates, the axes of said wire entry openings being angularly disposed with respect to the axis of the device; and a protective cover secured to said insulator body to enclose said terminal portions.

3. The electrical connector device defined in claim 2 wherein said clamping screws are positioned substantially tangent to said wire entry openings.

Patent No.

UNITED STATES PATENT OFFHIE CERTIFICATE OF CORRECTION Dated September 1 4, 197} It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2,

See

Column 3,

See

Column 3,

See

Column 3,

See

Column 4,

See

Column 4,

See

Column 5, before See claim 11, line 13 of amendment dated Dec. 8,

line

page

line

&5, "a" should be omitted after "of".

5, line 7, of specification, as filed.

7, line 1, of specification, as filed.

"mail" after "the should be --male- 50, "will" after "as" should be --will--.

7, line 28, of specification, as filed.

8, line 18, of specification, as filed.

--ashould be inserted after "is" 9, "drawing" should be --drawings-- 8, line 30, of specification, as filed.

53, "provided" should be --provides-.

10, line 13, of specification, as filed 13 (claim 1) --spring-- should be inserted "contact".

Column 6, line 8, "a at the beginning of the claim, should be -A--.

See claim 12, line 2 of amendment dated Dec. 8, 1970.

Signed and sealed this 28th day of March 1 972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. Attesting Officer ROBERT GOTTSGHALK Commissioner of Patents

Claims

1. A back-wired electrical connector body comprising: an insulator body including a terminal retainer element and a contact holder element secured thereto, said contact holder element having spring contact receiving chambers; plural terminal-contact members carried by said insulator body; each of said members having a terminal portion disposed in said insulator body and isolated from every other of said terminal portions; each of said terminal portions including axially extending mounting means and a binding plate which is angularly disposed with respect to said mounting means and the axis of the device; one of said terminal-contact members being a grounding member having contact portions and the others being line members having spring contact portions; said grounding member having keying means in the form of wider mounting means than said line terminal mounting means; said terminal retainer element including means to receive said wider mounting means; each of said members including keying feet extending laterally outwardly from the spring contact portions thereof, the keying feet located on said line members being aligned and the keying feet located on said grounding member being offset with respect to one another; one of said spring contact receiving chambers being a grounding contact receiving chamber and the others being line contact receiving chambers, said chambers including seats for receiving the respective keying feet so that the grounding spring contact portions may not be seated in any of said line contact receiving chambers and the line spring contact portions cannot be seated in said grounding contact receiving chamber; terminal clamping screws rotatably carried by said binding plates; clamping nuts threadedly engaged with said screws and nonrotatably mounted in said insulator body; radial openings formed in said insulator body to provide access to the heads of said terminal clamping screws; wire entry openings formed in said insulator body providing access for wire lead ends to said binding plates, the axes of said wire entry openings being angularly Disposed with respect to the axis of the device; and a protective cover secured to said insulator body to enclose said terminal portions.