US3795890A

US3795890A - Terminal connector

Info

Publication number: US3795890A
Application number: US00260643A
Authority: US
Inventors: Buren H Van
Original assignee: TRW Inc
Current assignee: Northrop Grumman Space and Mission Systems Corp
Priority date: 1972-06-07
Filing date: 1972-06-07
Publication date: 1974-03-05
Anticipated expiration: 1991-03-05
Also published as: GB1396484A

Abstract

A spring clip for securing a terminal connector to an apertured workpiece includes a shank portion having a pair of opposed legs carrying snap lugs disposed opposite internal openings in the legs. The lugs are compressible into the openings in the legs and toward each other during insertion of the shank portion in a workpiece aperture. Each of the lugs is formed as a U-shaped bight having a longitudinally tapered and transversely arced external surface which facilitates inward, camming compression of the lugs during shank insertion. While the lugs are resilient in the sense that they are compressible as aforesaid and will snap apart to engage the workpiece subsequent to full insertion, the U-shaped bight form provides for substantial rigidity in each lug per se which in turn provides for aggressive snap engagement of the workpiece. The workpiece engaging edges of each of the lugs are disposed at a relatively steep acute angle to the head of the clip to thereby render a given size clip effective for use over a relatively wide range of workpiece thicknesses and aperture widths and to automatically compensate for thickness variations adjacent the aperture of an individual workpiece.

Description

U United States Patent 1191 1111 3 795 90 v 9 9 Van Buren, Jr. Mar. 5, 1974 [54] TERMINAL CONNECTOR [75] Inventor: Harold S. Van Buren, Jun, [57] ABSTRACT Lexington, Mass.

- A spnng clip for securmg a termlnal connector to an [73] Assignee: TRW Inc., Cleveland, Ohio apeitured workpiece includes a shank portion having [22] Filed June 7 1972 a pair of opposed legs carrying snap lugs disposed opposite internal openings in the legs. The lugs are com- [21] Appl. No.: 260,643 pressible into the openings in the legs and toward each other during insertion of the shank portion in a workpiece aperture. Each of the lugs is formed as a U- [52] 339/217 24/73 shaped bight having a longitudinally tapered and [5]} Km on 9/10 transversely arced external surface which facilitates [58] Field of semen .11. isw i t i i z i l 269 271- camming cfmpressim the lugs 85/80, 51/41, 24/73 73 shank insertion. Wh1le the lugs are resilient 1n the sense that they are compressible as aforesaid and will snap apart to engage the workpiece subsequent to full [56] Reierences cued insertion, the U-shaped bight form provides for sub- UNITED STATES PATENTS stantial rigidity in each lug per se which in turn. pro- 3,226,145 12/1965 Goldberg l5l/4l.75 vides for aggressive snap engagement of the work- 24/73 MF piece. The workpiece engaging edges of each of the 1 i 5 1/19 so 339/217 5 lugs are disposed at a relatively steep acute angle to MeyCI'St.........'. S th ad of to the y render a given Size FOREIGN PATENTS OR APPLICATIONS effective for use over a relatively wide range of work- 1,217,3s2 12 1970 Great Britain 151 4175 Piece thicknesses and aperture WidFhS and automat- 523,865 4/1956 Canada 339/128 L w ly mpen a e for thickness vanations adjacent the Primary ExaminerJoseph H. McGlynn Attorney, Agent, or F irm-J ames R. OConnor, Hall & Houghton aperture of an individual workpiece.

3 Claims, 8 Drawing Figures 1 TERMINAL CONNECTOR BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates primarily to electrical wire terminal mounting clips of the type found in US. Art Class 338, Subclass 2l7, entitled Electrical Connectors with Contact or Connector Secured to Insulation.

2. Brief Description of the Prior Art The prior art includes a number of snap mounted clips of the type contemplated by the present invention. In most cases the retaining lugs or tabs of the clips are formed from material sheared from the spring legs of the clips and bent outwardly in a desired configuration from the external marginal edges of the legs (see US. Pat. Nos. 3,340,497; 3,421,135; 3,486,158; and 3,609,654). The individual legs of stock thickness are subject to accidental deformation, they provide sharp external edges which lead to binding or hang up during insertion, and they do not provide the combination of resiliency and rigidity necessary to effect a tight, rattlefree assembly with a workpiece. In the present invention, the retaining lugs are formed as longitudinal U- shaped bights and are disposed completely inboard of the external marginal edges of the legs. This configuration and location provides a more rugged clip yet one which is easier to seat in a workpiece aperture. Further the improved clip provides for a rattle-free assembly in that it has the capacity to compensate for thickness de viations in a given workpiece. Still further, the improved clip can be economically produced and provides a cost saving to the user in that a given size clip can be efficiently used over a substantially wide range of workpiece thicknesses.

SUMMARY OF THE INVENTION The illustrated embodiment of a terminal clip includes a head portion having a screw receiving socket and a pair of opposed spring legs extending perpendicularly from opposite marginal edges of the head portion. Each of the legs has an opening formed therein and each carries a snap lug joined to the leg at points substantially remote from the head portion and flaring outwardly and upwardly toward the plane of the head portion and terminating in a relatively steeply angled free edge disposed proximate to but spaced from the plane of the head portion. The snap lugs have the form ofa U-shaped bight and are disposed within imaginary planar extensions of the internal marginal edges of the legs defining the openings therein. Thus the lugs which are stiffened by the bight configuration and yet are sufficiently resilient to flex relative to the legs will be compressed into the openings in the legs and toward each other during insertion of the legs through an appropriately sized workpiece aperture and will snap outwardly away from each other to aggressively engage the remote surface of the workpiece when the head portion has bottomed on the confronting surface of the workpiece. The external surfaces of the lugs are longitudinally tapered and transversely arced to facilitate easy camming insertion in a workpiece aperture. The steeply angled surfaces ofthe free edges ofthe lugs render a given size clip effective for usage over a relatively wide range of workpiece thicknesses.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a top plan view ofa terminal clip according to the invention;

FIG. 2 is a side elevational view of the terminal clip as seen from the lower side of FIG. 1;

FIG. 3 is a side elevational view of the clip as seen from the right side of FIG. 1;

FIG. 4 depicts the terminal clip in transverse cross section during insertion into a workpiece aperture. a clamping screw threaded into the clip socket is depicted in full;

FIG. 5 is a top plan view of an assembly depicting the clip fully seated in a fragmentary portion of an apertured workpiece;

FIG. 6 is a section taken on line 6-6 of FIG. 5;

FIG. 7 is a view similar to FIG. 5 with the workpiece, as seen in FIG. 8, being of greater thickness than that depicted in FIGS. 5 and 6; and

FIG. 8 is a section taken on line 88 of FIG. 7 and additionally depicting a retaining screw fully turned into the clip socket and clamping a terminal connector to the clip.

DESCRIPTION OF A PREFERRED EMBODIMENT A terminal clip 2 according to the invention is fabricated from sheet metal, preferably a relatively high carbon steel which is blanked, formed and thereafter hardened by heat treating to provide increased strength and resiliency. The head portion 4 of the clip has a generally'centralized, apertured screw receiving socket 6 impressed therein. The head portion is generally rectangular and has planar workpiece engaging flanges 8 projecting from two of its opposite marginal edges.

The shank portion 10 ofthe clip includes a pair of opposed, axially extending, generally rectangular spring legs 14 which are bent downwardly from the other opposite marginal edges of the head portion and lie generally perpendicular to the head portion and terminate in free end portions 16 remote from the head portion. The free ends 16 of the legs are toed slightly inward toward the axis of the clip and each free end portion has a generally circular opening 18 formed therethrough.

Each of the spring legs 14 has a substantially rectangular, elongated opening 20 formed therein by the partial shearing of metal from the legs and the material so sheared is drawn outwardly of the plane of the legs and shaped in a predetermined form to provide resilient snap lugs 22. One end of each of the lugs remains joined to the respective legs at hinge webs 24 and the lugs are splayed outwardly of the legs and extend upwardly from the hinge webs back toward the plane of the head portion 4. The lugs 22 are formed in the configuration of generally .U-shaped longitudinal bights opening toward the openings 20 in the legs and toward each other, and each lug includes a back portion 26 and merging wings 28 which diverge from the back portion to free longitudinal edges 30 lying more closely proximate the plane of the legs. As is clearly seen in the drawing, particularly FIGS. 4, 3 and 6, the wings 28 have a generally triangular shape and the uppermost free edges 32 thereof lie at a relatively steep acute angle to the plane of the head portion 4. The merging, arcuate, external surfaces of the back portion 26 and wings 28 are seen to gradually taper from the free edges 32 of the wings back into the plane of the legs 14 at hinge webs 24. Since the lugs 22 lie opposite the openings in the legs 14, i.e., within imaginary planar extensions of the inboard edges of the legs defining said openings, the lugs are adapted to be pivoted about hinge webs 24 and thus to be collapsed or compressed inwardly toward each other and the longitudinal axis of the clip. While the snap lugs 22 are resilient or flexible in the sense that they will pivotally deflect at the hinge webs, the lugs per se are, however, substantially rigid throughout their length by reason of the U-shaped bight configuration thereof.

A clip according to the invention could undoubtedly be utilized in effecting connections in a number of different applications. It was, however, designed primarily for use in domestic appliances, particularly radio and television sets, as a means for connecting blade-type terminal wire connectors from an antenna lead to the receiver chassis. To that end the clip carries a pan head screw 34 which is turned into the socket 6 in the head portion 4. After the screw is threaded into the clip, one or more of the lead thread convolutions on the screw is distorted to inhibit subsequent disconnection of the screw from the clip. ln a typical installation the clip is mounted on the back closure panel, or an auxiliary panel fastened to the back closure panel, of the radio or TV set frame. Such panels are usually relatively thin and are fabricated from electrically nonconductive materials such as masonite, fiberboard, and tough, rigid, synthetic plastics.

Panel sections

36 and 36a in the drawing are representative of fragmentary portions of plastic back closure panels and each has an appropriately sized,

square aperture

38, 38a, respectively, formed therethrough. The width of the

apertures

38 and 38a is somewhat greater than the width of the head portion 4 of the clip measured between the marginal edges thereof joining the legs 14 and is somewhat less than the distance across the outboard edges of the flanges 8. The clip is secured to the back panel by inserting the inwardly toed free ends of the legs 14 into the panel apertures and forcing the head portion of the clip toward the confronting surface of the panel. As the legs proceed through the aperture, the lugs 22 are cammingly compressed toward each other and into the openings 20 in the legs until the back portions 26 of the lugs have fully passed through the panel aperture whereupon the lugs spring apart and engage the remote marginal edges of the panel aperture. Since the longitudinal tapered and transversely arced lugs 22 present ideal camming surfaces to the marginal edges of the panel aperture, progression of the shank into and through the aperture is smooth and unimpeded, Ergo, a relatively minimal insertion force is sufficient to seat the clip. By way of comparison, it will be observed that most of the patented prior art devices earlier mentioned present sharp, almost knifelike edges to the margins of the panel aperture. One will appreciate that sharp edges will tend to bite into and therefore bind up on the panel rendering insertion difficult and requiring the use of excessive insertion force which increases the possibility for damage to the clip or panel or both during assembly. The insertion force is maintained until the flanges 8 projecting from the head portion 4 of the clip bottom on the confronting surface of the panel, whereby the lugs and flanges cooperatively grip opposite sides of the panel at the edges of the aperture to effect a tight, rattle-free fastening.

From a comparison of FIGS. 6 and 8, the reader will observe that the extent of spring back of the lugs 22 responsive to full insertion of the clip in a panel opening is dependent upon the panel thickness adjacent the aperture and the width of the aperture. In FIG. 6 the lug spring back is considerable when the clip is mounted on a relatively thin panel 36 having a relatively wide aperture 38 and substantially the entire free angled edge 32 of each snap lug locates behind the remote panel surface with the points of the lugs at the apices of the triangular wings biting into the remote edge of the panel defining the aperture 38. Conversely in FIG. 8 wherein the same size clip is mounted on a thicker panel 36a having a narrower aperture 380, the extent of lug spring back is somewhat restricted in that the edge of the aperture 38a is engaged at points on the angled edges 32 of the lugs closey proximate the back portion 26. Regardless of the points of engagement, however, a tight, rattle-free connection is achieved by reason of the aggressive engagement of the panel by the relatively rigid snap lugs, which rigidity is, as aforesaid, directly related to the U-shaped bight configuration of the lugs. As the foregoing comparison clearly indicates, the invention provides not only an efficient terminal clip, but one which is somewhat universal in that a given size clip can be used over a significant range of mounting panel thicknesses and will automatically compensate for thickness variations in an individual panel.

After the clip is mounted on the back closure panel, wire leads to the TV or radio receiver may be inserted in the circular openings 18 and soldered to the legs 14, or, in the alternative, sleeve or clamp-type terminals may be telescoped over the free ends 16 of the legs. At any time thereafter, the antenna lead is connected to the clip by slipping the bifurcated end of the wellknown blade-type connector 40 over the screw shank beneath the screw head and tightening the screw to clamp the connector against the head portion 4 of the clip, as is best depicted in FIG. 8.

The foregoing description is illustrative of a preferred embodiment of the invention and a typical assembly in which the invention is utilized. [t is, however, contemplated that the invention will be useful in applications other than antenna terminal mountings and even in applications which do not involve an electrical connection. It is also contemplated that changes in and modifications of the preferred embodiment of the clip per se may be effected without departing from the scope of the invention. Those who seek a precise definition of the scope of the invention are therefore directed to the claims which follow.

I claim:

1. A spring clip adapted to be applied to a workpiece having an aperture therethrough comprising a head portion having means thereon for overlying the workpiece and means thereon for threadedly engaging a screw turned into said head portion, and an integral shank portion insertable through the aperture in the workpiece, said shank portion including a pair of opposed, axially extending, generally parallel legs bent downwardly from opposed outboard marginal edges of said head portion, each of said legs having material removed therefrom to provide openings therein, said openings being defined by longitudinal and transverse internal marginal edges of said legs, and a pair of opposed retainer lugs joined to said legs proximate their ends remote from said head portion, said lugs flaring outwardly from said legs generally back toward the plane of said head portion and being disposed opposite said openings in said legs and within imaginary planar extensions of said internal marginal edges of said legs, each of said lugs terminating in a free edge spaced from the plane of said head portion, said free edges being disposed at a relatively steep acute angle to the plane of said head portion, said lugs have external surfaces which are transversely arced and tapered longitudinally from said free edges toward the planes of said legs whereby said lugs present substantially smooth workpiece engageable surfaces facilitating passage of said shank portion through a workpiece aperture, said lugs per se being resiliently compressible toward each other to permit passage of the shank into a workpiece aperture and being resiliently expansible away from each other upon passage through the workpiece aperture to urge said free edges into aggressive engagement with the workpiece.

2. A spring clip according to claim 1 wherein each of said lugs is in the form of a longitudinally extending, substantially U-shaped bight opening toward the longitudinal axis of said clip.

3. A spring clip according to claim 1 wherein the end portions of said legs most remote from said head portion are toed inwardly toward the longitudinal axis of the clip.