US3918790A

US3918790A - Snap spade electrical connector

Info

Publication number: US3918790A
Application number: US479313A
Authority: US
Inventors: John Richard Filson
Original assignee: Minnesota Mining and Manufacturing Co
Current assignee: General Electric Co; 3M Co
Priority date: 1974-06-14
Filing date: 1974-06-14
Publication date: 1975-11-11
Anticipated expiration: 1992-11-11
Also published as: US3945709A

Abstract

A snap spade electrical connector wherein a generally flat Ushaped part is adapted to receive a lug in the bight therein, a pair of inward projections on the part being engageable with a passing lug to require flexure of the part, and work-hardened regions of the part assuring resilient resistance to repetition of such flexure.

Description

' United States Patent Filson Nov. 11, 1975 [54] SNAP SPADE ELECTRICAL CONNECTOR 955.747 4/1910 Barcy 339/257 7 2 t 33 2 [75] Inventor: John Richard FilsomMedford, NJ. H966 9/ 77 R [73] Assignee: Minnesota Mining and FOREIGN PATENTS OR APPLICATIONS Manufacturing p y Paul, 426.937 4/1935 United Kingdom 339/277 R Minn.

[22] Filed: June 1974 Primary E.\'aminer.loseph H. MCGlynn [21] Appl, N02 479,313 Atlorney. Agent, or FirmRobert K. Youtie [52] US. Cl 339/257; 24/257 R, 29/630 A;

113/119; 248/200; 339/278 R [57] ABSTRACT [51] Int. CI. I-IOIR 11/22 [58] Field of Search I 339/257, 277, 278, 252. A snap spade electrical connector wherem 21 generally fiat U-shaped part is adapted to receive 11 lug in the 248/73 R 13 200371 l/65.77/377 bight therein. a pair of inward projections on the part 5 21 being engageable with a passing lug to require flexure of the part. and work-hardened regions of the part as- [56] References Cited suring resilient resistance to repetition of such flexure. UNITED STATES PATENTS 7 Claims, 6 Drawing Figures 9ll032 2/I909 Dow 339/257 US. Patent Nov. 11, 1975 3,918,790

" SNAQSPAQE ELEc'rRIcAL CONNECTOR BA KGROUND or THE INVENTION it well kjnownito those versed in the art, there are Sp y to FIGS- and 6; a Spade Connector is prior art spade terminals deflectable for lug engagement; but such prior terminals have not proved entirely satisfactory .i'rr-use -For example, the requirement of resilience for;lug reception conflicts with that of deformability for" conductor connection, so that more expensive. materials-such as phosphor bronze, and the like need be used,.:together with costly annealing procedures, to'ac'hieve"the desired conflicting characteristics.

'Asi's'\ve'llknown, it" is often necessary to repeatedly replace and remove a connector with respect to'a lug, without wear or loss of resilience, which characteristicswre not readily and economically obu I prior art devices.

MMARY OF THE INVENTION is an important object of the present invention to provide a snap spade electrical connector of the type de scribed which overcomes the above-mentioned d ifticul ties,. p ermits of substantial savings in material costs-and manufacturing procedures by the use of relatively. soft 'brass, or the like, affording desirable conducto ifionnecting qualities, and which results in lug receivingcharacteristicspermitting of repeated lug s'napiengagenient and removal without appreciably det'racting' frorn theresilient, snap engagement and releasable holding qualities with respect to terminal posts, lugs,. e t'cetera:"- It is a more particular object of the present invention to provide"asnap'spade electrical connector having the "Bate? DjejscaIPTIoN OF THE DRAWINGS ElGml i's a topperspective view showing a spade connector constructed in accordance with the teachings of the present invention.

F1652 i's 'a top plan view showing the connector of Prof-I. I I I FIG 3 isa bottom plan view showing the connector of FIG; f V i i I Fl Gfi is atop perspective view showing a slightly modified embodiment of connector. 7 FI G, is atop perspective view showing another modified embodiment ofcorinector of the present n e rt; r

FIG. offs a transverse sectional view taken generally along theIi nes66 of each of FlGS. 2, 4 and 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now more particularly to the drawings, and

there generally designated 10, and may be integrally fabricated of a single sheet of suitable conductive material, such as relatively soft copper or brass, as by stamping and forming. More particularly, the spade connector 10 may include a generally flat or planar part 11 for receiving engagement with a desired stud, screw or lug. The flat lug engaging part 11 may be of generally U- shaped overall configuration for reception of a lug or stud, andmay be provided with an outwardly extending integral tubular formation or barrel part 12, for reception of an uninsulated or stripped conductor or wire (not shown). By suitable metal working techniques the spade connector 10 may be formed from an integral sheet of suitably deformable conductive material, say

of relatively inexpensive, soft copper or brass.

The planar or flat, U-shaped lug engaging part 11 may include a bight portion 15 having formed therein a generally arcuate cutout or lug receiving open region 16. Extending from opposite ends of the generally flat bight portion 15, generally coplanar therewith, are a pair of elongate side portions or legs 17, also substantially flat andcoplanar with each other and the bight portion 15. The legs 17 may be substantially identical to each other, but of opposite hand, extending longitudinally of each other from opposite ends of the bight portion 15 on opposite sides of said open region 16 and defining therebetween a longitudinally inwardly extending passageway 18 which opens into the open region 16. The laterally spaced legs 17 may each be provided at its outer end with a beveled or chamfered edge 19 convergent longitudinally inwardly along the passageway 18 and each terminating at its inner end in a generally flat inwardly facing surface 20. That is, a pair of surfaces 20 are provided, which surfaces are generally flat and in laterally spaced, opposed parallel relation with each other. From the inner ends of the facing surfaces 20 there extends an arcuate, generally circular, arcuate and U-shaped edge surface 21 bounding the open region 16 of bight portion 15. That is, the arcuate edge surface 21 extends between and terminates at its opposite ends at respective surfaces 20.

Viewed otherwise, the elongate legs or side pieces 17 of lug engaging part 11 may be considered as defining 1 therebetween the longitudinal passageway l8 communicating at its inner end with the open region 16; and, there may be provided on the inner edges of legs 17 a pair of opposed, inner projections 22 extending into the passageway 18 toward and terminating short of each other in the parallel, facing terminal surfaces 20. Thus, the inward projections 22 define a constriction 23 in the passageway 18, for purposes appearing more fully hereinafter.

The tubular portion or barrel part 12 is located outward of the bightportion 15, extending therefrom oppositely away from the legs 17. In particular. a merging portion or reduced neck 25 may extend outwardly from the bight portion 15, remote from the legs 17, and integrally joined with the tubular portion or barrel part 12.

As the hereinbefore described unitary connector 10 is fabricated of soft malleable or deformable material, a bare conductor may be inserted in the barrel part 12 and the latter crimped or swaged to provide a highly effective connection, both mechanical and electrical.

In addition. the lug engaging part is provided on one face. say the upper side as seen in FIG. I, with a pair of work-hardened regions 30. The regions 30 may be elongate, each extending generally along a respective leg and may be formed by compression of the material of the lug engaging part. That is. each of the work-hardened regions 30 may assume the form of an elongate groove 31 providing a compressed location formed by a suitable punching or coining tool.

In the embodiment of FIGS. I3, the compressed locations or work-hardened regions 30 are generally straight and extend along respective legs 17 into adjacent portions of the bight portion 15.

In use, upon snap engagement of the lug engaging part 11 with :1 lug or stud which enters through passageway 18, the lug or stud snap engages past the projections 22'. bearing against projection termini 20, and re I siliently flexing the part I]. This flexure is resiliently absorbed or taken up by the work-hardened regions 30, so that such resilient flexure may be obtained repeatedly upon snap engagement and disengagement of studs through passageway 18. That is, without the com pressed locations or grooves 31 defining work-hardened regions, the lug engaging part I] would relatively quickly loose its resilient action upon repeated snap engagement and disengagement with respect to a proper size stud. However. by the structured described hereinbefore, such repeated operation does not substantially deteriorate the resilient flexing action, while the relatively soft material of barrel part 12 achieves the desir able effective securement to a conductor.

Even in the absence of repeated resilient flexure, as described above, the criticality of close manufacturing tolerances is reduced by the instant invention. as enlarged tolerances are compensated for by the substantial resilient flexibility. all toward more satisfactory function and use. at lower manufacturing and selling costs.

As best seen in FIG. 6, the compressed locations or grooves 31, defining work-hardened regions 30, may be generally V-shaped in cross-section while of straight longitudinal configuration, the under surfaces of the legs 17, as at 32 being substantially flat or planar to insure work-hardening by compression in the region 30 without bulging on the under side. Also. the upper surface of legs 17, as at 33, adjacent to the grooves 31, is similarly flat. whereby pronounced compression and work-hardening of the material is effectively assured.

Considering the embodiment shown in FIG. 4, a snap spade electrical connector is there generally designated 100. including a generally flat, U-shaped lug engaging part 11a and extending integrally therefrom a tubular conductor receiving portion or barrel part 12a. The spade connector 100 may be essentially similar to the first-described spade connector in its generally coplanar bight portion 15:! and legs 170, including the. inner leg projections 22a. all corresponding respectively to the correspondingly numbered elements of the first described embodiment.

However. the spade connector 10a differs from the first described embodiment in that a pair of work-hardened regions a are of different configuration, being smoothly arcuate and extending along respective legs 17a into the adjacent portions of bight portion 15a, being generally concentric with lug receiving open region 16a. That is, thework-hardened regions 30a may be defined by elongate compressed locations 31a formed by suitably configured punching or coining tools. The smoothly arcuate compressed locations 311! I are believed to afford enhanced resilient reinforcement against flexure of the lug receiving part Ila. While the further snap spade electrical connector is there generally designated 10/), and includes a generally flat. U- shaped lug engaging part 111; having a generally flat bight portion 15b and a pair of generally flat elongate I legs 17b extending longitudinallyof each other from a opposite ends of the bight portion 15b substantially coplanar with the latter. A barrel part 12b extends integrally fromthe bight portion, 15b oppositely away from the legs 17]).

The legs 1717 may be considered as definining therei between an elongate passageway 1812, and the legs 17b provided with a pair of opposed inward projections 22b. A pair of elongate work-hardened regions 30b may be formed by punching or coining compressed locations or grooves 311; in respective legs 17b extending longitudinally therealong and into the adjacent portions of bight portion 15b.

Furthermore. there are provided additional pairs of opposed inner projections 35 on respective legs 17b ex tending into the passageway 18b toward and terminating short of each other to define an additional constriction 36. The additional pair of projections 35 and associated constriction 36 are located in spaced relationbetween the. first-mentioned projections 22!; and the bight portion 1511. As illustrated, the projections 35 maybe V pointed, or flattened, if preferred. v I There may be provided still another additional pair of opposed inner projections 37 on respective legs 17b defining still another passageway constriction. as at 38; which may be located in spaced relation between the projections 35 and bightportion 15b.

The spacing between the first-mentioned projections 5 22b, the additional pair of projections 35, and the lastmentioned pair of projections 37 may all be different; Thus, the passageway 18b may be of progressively smaller lateral dimension inwardly toward thebight portion 15. For example, the projections 2212 may be I spaced sufficiently to permit snap engagement thereby of a No. 10 stud for holding therein, while the next pair of projections 35 may be just sufficiently spaced for passage therebetween of a No. 8 stud for holding. therein, and the last-mentioned pair of projections 37 may be just sufficiently spaced for passage therebetween of a No. 6 stud for holding therein. t In addition to the above-mentioned advantageous results of the hereinbefore described embodiments, the embodiment of FIG. 5 furtherpermits of usage with a wide variety and range of sizes and types of studs and From the foregoing, it is seen that the present inven- 7 tion provides a snap spade electrical connector which is I extremely simple in construction, economic in manu facture, entirely reliablethroughout a long useful life.

and which otherwise fully accomplishes its intended objects.

Although the present invention has been describedin some detail by way of illustration and example for purposes of clarity of understanding, it is understood that certain changes and modifications may be made within the spirit of the invention.

What is claimed is:

1. A snap spade electrical connector comprising a generally flat U-shaped lug engaging part including a bight portion having a lug receiving open region. a pair of legs extending longitudinally of each other from opposite ends of said bight portion on opposite sides of said open region and defining therebetween a longitudinally inwardly extending passageway opening into said open region, a pair of opposed inner projections on respective legs extending into said passageway toward and terminating short of each other to define a passageway constriction, said legs and inner projections being generally flat and coplanar with said bight portion, and work-hardened regions extending longitudinally along each leg for enhanced resistance of the leg to repeated snap engagement of a lug throughsaid constriction, said work-hardened regions each comprising an elongate compressed location defining a surface groove on at least one side without increased leg thickness.

2. A snap spade electrical connector according to claim 1, said grooves being generally straight,

3. A snap spade electrical connector according to claim 1, in combination with a conductor receiving barrel part extending integrally from said bight portion away from said legs, said barrel part and lug engaging part being of relatively soft deformable material for LII good connection to a conductor in said barrel part with said legs being rigidified by said compressed locations for said snap lug engagement.

4. A snap spade electrical connector according to claim 1, in combination with an additional pair of 0pposed inner projections on respective legs extending into said passageway toward and terminating short of each other to define an additional passageway constriction, said additional pair of projections being coplanar with said legs and located in spaced relation between said first mentioned pair of projections and said bight portion, whereby lugs of one size are snap engageable through said first mentioned constriction and lugs of a different size are snap engageable through said additional constriction.

5. A snap spade electrical connector according to claim 1, said projections having their inner termini generally flat longitudinally of said passageway, to minimize wear upon said repeated snap engagement.

6. A snap spade electrical connector according to claim 1, said work-hardened regions each extending along a respective leg and into said bight portion.

7. A snap spade electrical connector according to claim 6, said work-hardened regions being smoothly

Claims

1. A snap spade electrical connector comprising a generally flat U-shaped lug engaging part including a bight portion having a lug receiving open region, a pair of legs extending longitudinally of each other from opposite ends of said bight portion on opposite sides of said open region and defining therebetween a longitudinally inwardly extending passageway opening into said open region, a pair of opposed inner projections on respective legs extending into said passageway toward and terminating short of each other to define a passageway constriction, said legs and inner projections being generally flat and coplanar with said bight portion, and work-hardened regions extending longitudinally along each leg for enhanced resistance of the leg to repeated snap engagement of a lug through said constriction, said workhardened regions each comprising an elongate compressed location defining a surface groove on at least one side without increased leg thickness.

2. A snap spade electrical connector according to claim 1, said grooves being generally straight.

3. A snap spade electrical connector according to claim 1, in combination with a conductor receiving barrel part extending integrally from said bight portion away from said legs, said barrel part and lug engaging part being of relatively soft deformable material for good connection to a conductor in said barrel part with said legs being rigidified by saiD compressed locations for said snap lug engagement.

4. A snap spade electrical connector according to claim 1, in combination with an additional pair of opposed inner projections on respective legs extending into said passageway toward and terminating short of each other to define an additional passageway constriction, said additional pair of projections being coplanar with said legs and located in spaced relation between said first mentioned pair of projections and said bight portion, whereby lugs of one size are snap engageable through said first mentioned constriction and lugs of a different size are snap engageable through said additional constriction.

5. A snap spade electrical connector according to claim 1, said projections having their inner termini generally flat longitudinally of said passageway to minimize wear upon said repeated snap engagement.

7. A snap spade electrical connector according to claim 6, said work-hardened regions being smoothly arcuate.