US3408620A - Pressure pad type wiring terminal - Google Patents

Description

L A N T. M DH E T6 O N ARl II., Mw6 AEy Dwm .TJ Dd Rm@ .l En? R U s S E R P 8 6 9 l 9, 2 t C O firma/Myst United States Patent Hubbell, of Connecticut Filed July 6, 1966, Ser. No. 563,233

6 Claims. (Cl. 339-272) ABSTRACT 0F THE DISCLOSURE An ank This invention relates to improvements in electrical wiring terminals, and more particularly, clamp-type terminals improved pressure One of the known and a Inountlng means therefor opwith said undercut portion so as to front of said ange eratively associated wherein:

1s a plan View taken substantially along line 1-1 of FIG. 2 showing an electrical p the clamp type in accordance with the present invention with portions of conductor wire attached;

FIG. 2 is a front elevational view taken substantially along line 2-2 of FI 1 showing a conductor wire clamped by a pressure pad;

FIG. 3 is an elevational view taken substantially along line 3`3 of FIG. 2;

FI 4 is an enlarged perspective view showing the pressure pad alone removed -from the terminal assembly; and

FIG. 5 is a screw.

With particular reference to FIGS. 1 and 2, an electrical wiring terminal companyin g drawing,

perspective view of the improved clamping engaged in the screws 16 having the kerfed screw heads 32 and threaded Shanks 34. Each shank 34 is provided with pressure pad, screw shank.

Each pressure pad comprises: a v bottom wall 40;

bent normal to the upstanding wall, limit ends 46, each describing an Iacute angle with its tion results in ya screw mounting that insures that thepressure pad cannot be inadvertently lost or removed. The free end edges of ends 46 prevent such removal by digging into the portion 36, unless the legs 44 are intentionally separated.

, When assembling the electrical wiring terminal of the present invention, the screws -16 are individually inserted into and threadedly engaged in openings 30 so that the undercut portion 36 of the screw shank is located on the inte-rior of the terminal block 14. During such insertion, retaining Aiianges 38 freely pass through openings 30. Then the pressure pad 18 is slipped longitudinally in and through an open end of the terminal block, and the deflecting arms are aligned with andl snapped about the undercut portion 36. With the pad thus rotatably seated onthe end of the screw shank, the bared stranded ends 12 of the cable 10 may be inserted longitudinally in the tubular terminal block and disposed adjacent bottom wall 24, and the screws 30 are further threadedly advanced into the-terminal block until the bottom walls 40 of the pressure pads are brought to bear on the wire ends 12 to firmly clamp them in position against bottom wall 24, which then constitutes a clamping wall. It can be clearly seen that as the screws 30 are rotated, the pressure pads 40 mounted thereon will not rotate but will merely exert a downward force on the wire ends. Therefore, in clamping the wire ends in the terminal, the -action of the pressure pads is such as to produce effective compressive clamping without undesirable twisting of the wire ends.

lAlthough the improved clamping screw and pressure pad means of the present invention has been described in use in a terminal block assembly, it will be understood that I have not comprehended to limit its use to such an environment. On the contrary, this improved clamping screw has application in innumerable electrical wiring terminal uses wherein a screw may be threadedly mounted in position to clamp a conductor wire end against a terminal clamping wall.

It is 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 spirit and scope of the invention as hereinafter claimed.

What Patent of the United States is:

1. For use in an electrical terminal having a terminal clamping wall, and a threaded opening means for supporting a threaded clamping screw in position to clamp a conductor wire end against the clamping wall, an improved clamping screw comprising: a threaded shank; a head at one end of said shank; a plain undercut portion, at the end of said shank opposite said head, of smaller diameter than said shank and terminating in a larger diameter retaining ange which is of smaller diameter than said shank; anda pressure pad mounted on said shank including a planar pressure wall disposed in front of said I claim as new and desire to secure by Letters disposed substantially normally to said pressure wall, and a mounting means therefor including a plurality of deliecting arms disposed substantially normally to said wall portion and overlying said press re wall, each arm having its major width diavai-52011 ,y A'

CII

4 mension extending in a directionnormal to the plane of said pressure wall and its minor width dimension extending in the direction of detiection, and securing means positioned at the ends of said arms, whereby said pressure pad may be operatively associated with said undercut portion' so' as to be mountable .therecjn' by"r`e`lative lateralY movement of said mounting means and saidiu'n'deri cut portion.` IMI 2. An improved, electrical wiring terminallfc'oinprising: threaded opening meansg'at leastoneclamping wall portion; at least one clamping screw as defined in claim 1 arranged to be threadedly engaged in said threaded opening means with said pressure pad disposed to move toward and away romsaid clamping wall portion.

. 3. The improved electrical terminal clamping screw ned in claim 1 wherein said pressure pad is constructed of spring metal.

4. For use in an electrical terminal having a terminal;

a l threaded `opening means clamping screw clamping wall and porting a threaded a conductor wire proved clamping screw comprising: a threaded shanki'a head at one end of said shank;` a'plain undercut portion, at the end of said shank opposite said head, of smaller diameter than said shank and terminating in a larger diameter `retaining ange which is of smaller `diameter than said shank', and a pressure pad mounted onsaid shank and including a planar pressure wall, a wall portion disposed substantially normally ito said pressure wall, and mounting means including a pluralityv of deliecting arms disposed substantially normally to said wall portion `and overlying said pressure wall, said deectingarms being provided with camming portions at their ends,'said camming portions lforming acute angles with said detiecting arms.

5. The improved electrical terminal clamping screw deined in claim 4 wherein said pressure pad is constructed of spring metal.

6. An improved electrical wiring terminal comprising:`

toward and4 away from said clamping wall portion.

Referencesl Cited UNITED STATES PATENTS 2,161,249 `6/ 1939 Dibner 339-272 2,203,337 6/1940 Mebold 339-244 2,602,104 7/ 1952 Hubbell et al. 339--272 2,693,585 11/1954 Mason 339-272 X 2,877,440 3/ 1959 Dorjee 339-272 X 3,346,835 10/ 1967 Burniston 339--272 OTHER REFERENCES German Printed Application DAs 1,104,013, Apr. 4,V

1961, Schulz et al German Printed Application DAS 1,116,294, Nov, 11,

1961, Eisert.

MARVIN A. CHAMPION, Primary Examiner. P. TEITELBAUM, Assistant Examiner.

in position to clamp end against the clamping wall, an

directed towardeach other and`

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