US3804971A

US3804971A - Solderless wire connector

Info

Publication number: US3804971A
Application number: US00259653A
Authority: US
Inventors: J Bazille
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: 3M Co
Priority date: 1971-06-28
Filing date: 1972-06-05
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16

Abstract

A solderless wire connector including a first connector member having wire receiving channels, and a second connector member mounted on the first connector member for relative movement from an open position to a closed position to engage a contact element carried by the second connector member with wires in the channels. Latching projections, interacting between the connector members to define the positions thereof, afford movement of the connector members to a partially closed position by finger pressure. At the partially closed position retaining members within the connector engage and retain wires within the channels to facilitate use of a pliers for further movement of the connector members to their closed position.

Description

United States Patent Bazille, Jr.

SOLDERLESS WIRE CONNECTOR [75] Inventor: James H. Bazille, Jr., Village of North St. Paul, Minn.

[73] Assignee: Minnesota Mining and Manufacturing Company, St. Paul, Minn.

[22] Filed: June 5, 1972 [21] Appl. No.: 259,653

Related US. Application Data [63] Continuation of Ser. No. 157,275, June 28, 1971,

abandoned.

[52] US. Cl. 174/88 R, 174/98 [51] Int. Cl H02g 15/08 [58] Field of Search 174/88 R, 92, 84 R; 339/95 R, 97 R, 98, 99 R, 95 A [5 6] References Cited UNITED STATES PATENTS 3,012,219 12/1961 Levin et a1 174/92 X 3,118,715 l/l964 Potruch 339/98 [451 Apr. 16,1974

I 3,147,338 9/1964 Ekvallet a1 ..174/92X 3,162,501 12/1964 Wah1..; ..339/98 Primary Examiner-Darrell L. Clay DeLal-Iunt 5 7 ABSTRACT A solderless wire connector including a first connector member having wire receiving channels, and a second connector member mounted on the first connector member for relative movement from an open position to a closed position to engage a contact element carried by the second connector member with wires in the channels. Latching projections, interacting between the connector members to define the positions thereof, afford movement of the connector members to a partially closed position by finger pressure. At the partially closed position retaining members within the connector engage and retain wires within the channels to facilitate use of a pliers for further movement of the connector members to their closed position.

6 Claims, 8 Drawing Figures PATENTEDAPR 1 m4 3804.971

D/ELfC TR/c GREASE F/LLED INVENTOR.

5 JAMES H BAZ/LLE JR. WW la 1 M mffflza iw A 7' TORNE vs SOLDERLESS WIRE CONNECTOR CROSS REFERENCE This application is a continuation of application Ser. No. 157,275, filed June 28, 1971, now abandoned.

FIELD OF THE INVENTION The apparatus of this disclosure relates to solderless wire connector assemblies such as may be used for DESCRIPTION OF THE PRIOR ART Many prior art solderless wire connectors include a first connector member having wire receiving channels, and a second connector member carrying a conductive metal contact element. The connector members are relatively movable from an open position at which the contact element is spaced from the wire receiving channels, to a closed position at which spaced extending legs of the contact element are transverse of the channel and inengagement with electrical wires in the channels so that an electrical contact is made therebetween. Latching projections interacting between the connector members are also provided to define the open and closed positions of the connector members, and to lock the connector members in their closed position.

Connectors of this type typically require the use of a plier like tool to move the connector members to their closed position. Thus, a workman'must insert wires into the channel, and maintain the wires in position with one hand while with the other he grasps the tool, engages it with the connector, and squeezes the connector members to their closed position. Such manipulation is difficult, and occasionally a wire becomes displaced during this operation which may result in a defective connection.

A second problem presented by some prior art connectors is the possibility that wires inserted in the channels will be misaligned with respect to the contact element during closing of the connector so that an end of a leg on the contact element may strike and sever the wire. v

Additionally, many prior-art connectors of the type which connect a continuing or run wire to a terminating or tap wire have not afforded a sufficiently tight enclosure when in the closed'position to restrict erosion of dielectric grease is typically placed around the contact element to protect the electrical connection when the connector is exposed to moisture.

SUMMARY OF THE INVENTION The present invention is a connector of the type previously described having two members relatively movable to engage a contact element with wires in channels in the connector, and having latching projections to define the positions of the connector. Unlike the prior art, however the connector of the present invention has a partially closed position between the open and closed positions at which the connector members will be releasably maintained by the latching projections and at which retaining members within the connector engage and hold the insulation on wires within the channels. The connector members may be moved to the partially closed position by the use of finger pressure. Thus, after a craftsman has manually positioned the wires within the connector he may move the connector members to their partially closed position with only finger pressure from the hand holding the connector, and thus ensure proper retention of the wires within the connector while a plier-like tool is applied to fully close the connector.

Additionally, in the connector according to the present invention, the retaining members guide the wires within the channels between the legs of the contact element during closing of the connector, thus preventing the severing of the wires by the ends of the connector legs. Also, the retaining members grasp the insulation on each wire and restrain movement of wires at the contact element and thus minimize the possibility of the wires breaking at the connection with the'contact element.

The novel construction of the connector members also affords a full length opening along one side of at least one of the channels so that a length of a continuing wire may be inserted while the connector is open. The opening is entirely closed when the connector is closed, and the connector members provide a tight enclosure to restrict the erosion of dielectric grease from around the contact element.

BRIEF DESCRIPTION OF THE DRAWING This invention will be more fully understood after reading the following description which refers to the accompanying drawing in which like numerals designate like parts throughout the figures and wherein:

FIG. 1 is an exploded perspective view of a preferred embodiment of a connector according to the present invention, with a first member inverted to illustrate the internal interacting portions of the connector;

FIG. 2 is a top view of the connector of FIG. ll;

FIG. 3 is a view partially in section taken approximately along the lines 3-3 in FIG. 2 and illustrating the members of the connector in an open position;

FIG. 4 is a view partially in section taken approximately along the lines 3-3 in FIG. 2 and illustrating the members of the connector in a partially closed position;

FIG. 5 is a view partially in section taken approximately along the lines 3-3 in FIG. 2 and illustrating the members of the connector in a fully closed position;

FIG. 6 is a sectional view, with some parts shown in elevation, taken approximately along lines 6-6 of FIG.

FIG. 7 is a sectional view taken approximately along lines 7-7 of FIG. 6; and

FIG. 8 is a sectional view taken approximately along lines 88 of FIG. 6.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawing there is shown a solderless wire connector according to the present invention for electrically connecting a continuing or run wire 22 to a terminating or tap wire 23 (see FIG. 2). The connector includes an insulating resilient first or body member 10 having a wire receiving channel 48 for receiving the run wire 22 and a wire receiving channel 49 for receiving the tap wire 23, and having a first set of outwardly extending latching projections Ill, 62, and 63. An insulating resilient second or cap member 12 is mounted on the body member 10 forrelative movement from an open position (FIG. 3) to a closed position (FIG. 5) and has a second set of inwardly extending

latching projections

40 and 41 which interact with the

latching projections

11, 62, and 63 on the body member to define the open and the closed positions of the body and

cap members

10 and 12, and to lock the body and

cap members

10 and 12 in their closed position. A plate-like metal contact element 26 (FIG. 8) is mounted on the cap member 12 and has spaced extending legs 29 defining wire receiving recesses 31 therebetween. The contact element 26 is spaced from the

wire receiving channels

48 and 49 when the body and

cap members

10 and 12 are in the open position, and the legs 29 of the contact element are transverse of the

channels

48 and 49 in a groove or furrow in the body member 10 when the body and

cap members

10 and 12 are in the closed position to engage and make an electrical contact between

electrical wires

22 and 23 within the

channels

48 and 49.

The body and

cap members

10 and 12 of the novel connector according to the present invention may be moved by finger pressure from their open position (FIG. 3) to a partially closed position (FIG. 4) during which movement a plurality of retaining member or fingers 37 mounted on the cap member 12 position the

wires

22 and 23 in the proper position for subsequent engagement by the legs 29 of the contact element 26 and engage the

wires

22 and 23 to retain the

wires

22 and 23 in a fixed longitudinal direction within the

wire receiving channels

48 and 49. The first and second sets of latching projections '11, 62, 63, 40 and 41 interact to releasably maintain the body and

cap members

10 and 12 at their partially closed position (FIG. 4), so that the

electrical wires

22 and 23 are retained within the

channels

48 and 49 prior to further movement of the body and

cap members

10 and 12 to their closed position by the use of an auxiliary tool (not shown).

To assist in the understanding of the preferred embodiment illustrated in FIGS. l-8, it will be assumed that the solderless electrical wire connector will be assembled by the body member 10 being vertically pressed down into the cap member 12, as shown by the dotted lines and arrows of FIG. 1, and reference will be made to this vertical orientation, e.g., top and bottom, throughout the description and claims; the end and side references will correspond to the normal description of an elongated box-like object. It is understood, of course, that the directional orientation of the connector, i.e., vertical, top, bottom, side, and etc., does not limit the assemblage nor the utility of the connector to the stated orientation but has been utilized only to facilitate the understanding of the invention.

Referring now to FIG. 1, the cap member 12 is made from a resilient insulating material formed into two side walls 14, two

end walls

16, 17 and a bottom plate 18. The

end walls

16, 17 have

apertures

19, 20, respectively, to provide clearance for the run wire 22 and tap wire 23 (not shown in FIG. 1). Integrally formed with the side walls 14 and the bottom plate 18 are abutments 24 (see FIGS. 3, 4, 5 and 8). Each abutment 24 has a vertical groove with a width approximating the thickness of the metal contact element 26 to receive and maintain the contact element 26 in a vertical relationship relative to the cap member 12. The distance between the corresponding grooves approximates the width of the element 26 between the outer edges of the cesses 31. The distal ends of the legs 29 diverge to define divergent openings 32, which opening 32 the recesses 31 to assist in guiding the

wires

22 and 23 in the

wire receiving channels

48 and 49 into the recesses 31. The opening parallel edges ofthe legs 29 are separated by a distance somewhat less than the diameter of the smallest wire conductor to which connection is to be made. When the body and

cap members

10 and 12 of the connector are in their partially closed position as shown in FIG. 4, the divergent ends of the legs 29 come into contact with the

wires

22 and 23 and guide the

wires

22 and 23 into the recesses 31. Upon further partial closing the

wires

22 and 23 are pressed into the recesses 31, and the opposing edges of the legs 29 which define each recess 31 cut into and through the insulation around the

wires

22 and 23 and bear against the conductors 33 of the

wires

22 and 23. The conductors 33 spread the resilient legs 29 from their original position so that the legs 29 in attempting to spring back toward their original position exert a continued pressure against the conductors 33 and maintain a spring reserve electrical contact therebetween. The overall width of the contact element 26 adjacent the legs 29 is less than the internal distance between the side walls 14 (see FIG. 8) to allow the legs 29 to be resiliently spread apart without interference from the side walls 14 and to prevent the spread legs 29 from cutting into or through the walls 14 to lessen the electrical insulating property of the connector. Connections made in this manner, have been tested and. found to provide unusually low resistance that lasts despite mechanical stresses, or temperature and pressure changes.

Spaced from and on opposite sides of the contact element 26 are a pair of slotted wire supports 34 (see FIG. 1) integrally formed with the side walls 14 and the bottom plate 18, and having slots 35, which are in line with the recesses 31 (see FIG. 3). The slots 35 are defined by upwardly extending fingers 37 the opposed edges of which diverge at the ends of the fingers 37 to provide diverging openings 38. The sloping edges defining the openings 38 act to guide the

wires

22 and 23 in the

wire receiving channels

48 and 49 into the recesses 31 and slots 35 when the connector is being closed (see FIGS. 3, 4 and 5). The opposed edges of the fingers 37 defining the slots 35 are spaced apart slightly less than the outside diametrical dimension of the smallest wire to which connection is to be made. As the wires are forced into the slots 35, the interference between the

wires

22 and 23 and the edges of the fingers 37 cause the resilient fingers 37 to deflect. This resilient deflection maintains a spring reserve tight grasp on the insulation (see FIG. 6) to maintain the

wires

22 and 23 within the

wire receiving channels

48 and 49 when the members l0 and 12 of the connector are in the partially closed position, and to minimize the stress in the conductors 33 at the contact element 26 after the connector is closed. Clearance is provided between the projecting portion of the fingers 37 and the side walls 14 to permit the deflection of the fingers 37.

The body member is preferably made from a relatively transparent insulating material formed into a four cornered generally block-like configuration having a base portion 44 and two

end walls

46 and 47. Extending through

end walls

46 and 47 is the channel 48 to receive the run wire 22. Extending through wall 47 and partially through wall 46 is the channel 49 to receive the tap wire 23. The end wall 46 includes an interior stop surface 50 and a deflectionplate 51 (see FIG. 2) within the channel 49 to prevent the tap wire 23 from extending beyond the end of the body member 10. The deflection plate 51 acts to vertically deflect the end of the wire 23 toward the surface 50 and thus bind the end of the wire 23 within the wall 46. Between the end walls and extending from the base portion are two plate-like beams 52. Each beam 52 is spaced from the

adjacent end wall

46 or 47 to define an elongated hollow therebetween to receive a different one of the slotted supports 34. Each beam 52 has a width slightly less than the distance between the element 26 and the supports 34 on the cap member 12 to fit therebetween (see FIG. 6). The two beams 52 are spaced apart to form a groove or furrow therebetween transverse of the

wire receiving channels

48 and 49 to receive the contact element 26. Semi-circular seats 53 defining a portion of the

channels

48 and 49 support the

wires

22 and 23 as the same are forced into the recesses 31 and slots 35. Within the furrow are two stuffer bars 55 in line with the recesses 31 (see FIG. 8) and each having a width less than the distance between legs 29 to readily enter the recesses 31 and force the

wires

22 and 23 into the recesses 31 in the contact element 26. Within each hollow between one of the beam 52 and the

end wall

46 or 47 adjacent thereto are two posts 57 in line with the slots 35 (see FIGS. 3-5) to force the

wires

22 and 23 into the slots 35 of the wire supports 34. The stuffer bars 55 and posts 57 extend downwardly toprovide a lower surface coinciding with the upper surface of each

channel

48 and 49. u i

The

end walls

46 and 47 of the body member 10 carry the second set of latching projections including an upper set of four projections 11, and a lower set of projections consisting of four pairs of

ears

62 and 63. The

projections

11, 62 and 63 interact with the

projections

40 and 41 of the first set of latching projections to provide detent means for defining the open (FIG. 3) and partially closed (FIG. 4) positions of the connector, and provide locking means to lock the connector in its closed position (FIG. 5). In the open position (FIG. 3) the

ears

62 and 63 on the body member 10 are positioned in the space between the

projections

40 and 41 on the cap member 12. Upon sufficient pressure on the body and

cap members

10 and 12 to move the

ears

62 and 63 past the projection 41, the cap and body members will move to their partially closed position (FIG. 4) with the

projections

40 and 41 on the cap member 12 in the space between the ears 63 and the projections 11. In the partially closed position the upper cars 63 abut the lower projections 41 and the upper projections 40 abut the ramp surfaces 58 so that the reacting forces against the upper ears 63 and the ramp surfaces 58 tend to retain the body and cap members l0 and 12 in this partially closed position. As shown in FIG. 4, the

wires

22 and 23 are partially wedged into the recesses 31 and slots 35 and are thus retained within the connector. Finger pressure of the craftsman is sufficient to press together the body and

cap members

10 and 12 from the open to this partially closed position. With the wires thus retained within the connector, the craftsman may release his finger grip on the connector without the wires readily separating from the connector, and can substitute a plier-like crimping tool for his fingers to move the body and

cap members

10 and 12 of the connector to the fully closed position shown in FIG. 5 so that the legs 23 of the contact element 26 will sever the insulation and make electrical contact with the conductors 33 of the

wires

22 and 23. Upon such movement of the body and

cap members

10 and 12, the resilient walls 14 of the cap member 12 will deflect outwardly via a camming action of the projection 40 against ramp surfaces 58 on the projections 11, and in the fully closed position of the members the projections 40 under the influence of the resilient walls 14 will seat over the projections 11 in recesses 59 in the 7 body member 10 to lock the connector in the fully closed position.

Extending from the end wall 47 about the channel 4 is a semi-circular plate 64 which provides additional support to the tap wire 23 and identifies, for the craftsman, the channel which is to receive the tap wire 23.

The body member 10 has a transverse side opening 60 communicating with the channel 48 to permit a length of the continuing run wire 22 to be laterally inserted into the channel 48 when the body and

cap members

10 and 12 are in their open position (FIG. 3). The ramp surfaces 53 on the projections 11 assist in guiding the run wire 23 into the channel 46. As may be seen in FIG. 5, the side opening 60 for the run wire 22 is covered along its entire length by the adjacent wall 14 when the body and

cap members

10 and 12 are in their closed position.

Before assembling the connector, a quantity of relatively transparent dielectric grease (not shown) is preferably inserted into the cap member 10 around the contact element 26. When the body and

cap members

10 and 12 are locked in their fully closed position an enclosure is provided about the dielectric grease by the wire supports 34, bottom plate 18 and side walls 14 of the cap member 12, and the base portion 44 of the body member 10, thus protecting the dielectric grease from erosion when the connector is exposed to moisture.

As a specific illustrative but non-limiting example of a preferred embodiment adapted for use in connecting 22 through 23 gauge insulated copper wire, a connector is constructed as follows: the body member 10 is molded from a transparent polycarbonate to have an over-all length of 1.1 l centimeter (.44 inch), an overall width of .64 centimeter (.25 inch), and an over-all height of .56 centimeter (.22 inch). The

longitudinal channels

46 and 49 have a diameter of .13 centimeter (.05 inch). The cap member 12, also formed of polycarbonate, has an over-all length of .95 centimeter (.38 inch), an over-all width of .80 centimeter (.32 inch), and an over-all height of .60 centimeter (.24 inch). The plate-like slotted supports 34 each have a thickness of .066 centimeter (.026 inch) and are formed with the fingers 37 defining .036 centimeter (.014 inch) slots 35 therebetween with a 40 taper on the side fingers and .06 centimeter (.03 inch) radii on the central finger. The metal contact element 26 is formed from a copper alloy No. 260, having an over-all height of .38 centimeter (.15 inch), an over-all width of .52 centimeter (.20 inch), a thickness of .04 centimeter (.016 inch), with legs 29 defining .024 centimeter (.009 inch) recesses 31 therebetween with 50 tapers at the leading edge of the opening 32.

It will be appreciated in view of the foregoing description that the illustrated vertical orientation of the body and

cap members

10 and 12 allows a craftsman to view down into the connector through the transparent body member 10, to check the alignment of the wires and the recesses before the connector is crimped together, as the connector would be normally held by a craftsman; however, the cap member 12 could also or alternatively be transparent wherein it may be desired to view through the cap member 12 as the same is pressed down over the body member 10.

Having thus described the invention with reference to a preferred embodiment, what is claimed is:

1. ln a solderless wire connector adapted for electrically connecting at least two electrical wires each having a metal conductor and an insulating coating thereabout, said connector comprising:

an electrically insulating resilient first connector member having parallel wire receiving channels and a groove extending perpendicular to said channels, said first connector member having a first set of latching projections;

an electrically insulating resilient second connector member mounted on said first connector member for movement relative thereto from an open position to a closed position, and having a second set of latching projections interacting with said first set of latching projections to define said open position and to lock said connector members in said closed position upon movement thereof to said closed position; and

a metal contact element mounted on said second connector member and having spaced extending legs defining parallel wire receiving recesses therebetween, said contact element being spaced from said wire receiving channels when said connector members are in said open position and being transverse of said channels in' said slot when said connector members are in said closed position to engage and make electrical connection between electrical wires within said slot;

the improvement wherein said sets of latching projections include cooperating projections to releasably retain said connector members at a partially closed position between said open and closed positions; said connector includes retaining members adapted to engage the insulating coating on wires in said channels when said connector members are in said partially closed position to retain the electrical wires within said channels and in alignment with said contact element; and said latching projections and said retaining members are adapted to afford movement by finger pressure of said first and second members from said open position to said partially closed position.

2. A connector according to claim 1 wherein said retaining members are formed on said second connector member and comprise spaced extending fingers defining parallel slots, said fingers being positioned with said slots in alignment with said recesses in said contact element and being positioned transverse of said channels to engage wires in said channels when said connector members are in said partially closed position.

3. A connector according to claim 2 including two retaining members spaced on opposite sides of said contact element, with the distal ends of said fingers defining diverging openings into said slots adapted to engage wires in said channels and align said wires with the recesses in said contact element during movement of said connector members from said open position to said partially closed position.

4. A connector according to claim 1 wherein said connector is adapted for making an electrical connection to a continuing wire, said first connector member has a transverse opening communicating with one side of one wire receiving channel adapted for receiving a length of a continuing wire, and said second connector member includes a wall spaced from said opening to afford positioning a length of a continuing wire in the channel when said connector members are in said open position, and positioned to entirely close said transverse opening when said connector members are in said closed position.

5. A connector according to claim 4 wherein said connector members have interfitting walls which provide a generally complete enclosure about said contact element when wires are positioned in said connector and said connector members are in their closed position, said closure being useful for retaining a quantity of dielectric grease around the contact element.

6. Aconnector according to claim 1 wherein said first connector member includes bars in said groove across said channels, each bar having a width less than that of said recesses, having a surface generally coplanar with the surface of a said channel opposite said contact member, and being oriented to enter one of the recesses and force a wire within the channel into said recess when said connector members are moved to their closed position.

Patent No. 3,8on,'97 I nated g il 16, 197 4 Inventor) James H. Bazille, Jr.

It is certified that error appears in the above-identified patent and that said Letters Patent ere hereby corrected as shown below:

- Column 1, line 50, delete "15; and line 56 after "two" insert connector Column 3 line 25, change "member" to members I Column '4, lines 12 and 13, change "divergentopenings 32, which opening 32 the recesses 31 to assist" to read divergent openings 32 to the recesses 31, which openings 32 assist Column 5,' line 35, change "beam" to beams Signed and sealed this 1st day of October 1974.

(SEAL) Atteat:

McCOY M. GIBSON JR; c. MARSHALL DANN Attesting Officer Commissioner of Patents FORM PO-lOBO (O-9) James H. Bazille, Jr.

Inventofls) the above-identified patent It is certified that error appears in "rented as shown below:

and that said Letters Patent are hereby cor Column 1, line 50, delete "is; and line 56, after "we" insert connector Column 3, line 25, change "member" to members Column 4 lines 12 and 13, change "divergent-openings 32, which opening 32 the recesses 31 to assist" to read divergent openings 32 to the recesses 31, which openings 32 assist Column 5, line 35, change "beam" to beams.

Signed and sealed this 1st day of October 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. Attesting Officer C. MARSHALL DANN Commissioner of Patents FORM PO-tOflO H049) UscomM-oc 60376400 I 0.8. GOVIIIIII!" PMIYING OHM! i0 O-db-"l.

Claims

1. In a solderless wire connector adapted for electrically connecting at least two electrical wires each having a metal conductor and an insulating coating thereabout, said connector comprising: an electrically insulating resilient first connector member having parallel wire receiving channels and a groove extending perpendicular to said channels, said first connector member having a first set of latching projections; an electrically insulating resilient second connector member mounted on said first connector member for movement relative thereto from an open position to a closed position, and having a second set of latching projections interacting with said first set of latching projections to define said open position and to lock said connector members in said closed position upon movement thereof to said closed position; and a metal contact element mounted on said second connector member and having spaced extending legs defining parallel wire receiving recesses therebetween, said contact element being spaced from said wire receiving channels when said connector members are in said open poSition and being transverse of said channels in said slot when said connector members are in said closed position to engage and make electrical connection between electrical wires within said slot; the improvement wherein said sets of latching projections include cooperating projections to releasably retain said connector members at a partially closed position between said open and closed positions; said connector includes retaining members adapted to engage the insulating coating on wires in said channels when said connector members are in said partially closed position to retain the electrical wires within said channels and in alignment with said contact element; and said latching projections and said retaining members are adapted to afford movement by finger pressure of said first and second members from said open position to said partially closed position.

6. A connector according to claim 1 wherein said first connector member includes bars in said groove across said channels, each bar having a width less than that of said recesses, having a surface generally coplanar with the surface of a said channel opposite said contact member, and being oriented to enter one of the recesses and force a wire within the channel into said recess when said connector members are moved to their closed position.