US2424444A - Spring binding post - Google Patents

Description

Patented July 22, 1947 2,424,444 SPRING BINDING POST Benjamin Fox, Philadel mesne assignments, t

Wayne, Ind.

phia, Pa., assignor, by Hugh H. Edy, Fort Application August 23, 1943, Serial No. 499,673

1 Claim. (Cl. 173-259) This invention relates to binding posts, and is particularly directed toward improvements on the binding post shown in United States Patent No. 2,293,719 of Hugh H. Eby.

The binding post according to this patent has been characterized by the provision of a solid fixed base having a peripheral groove, two (preferably) axial grooves in the outer surface intersecting the peripheral groove, and a through bore intersecting the meeting point of the axial and peripheral grooves. A sheet metal cap having round apertures and a closed end was of the base compressing a spring between the closed end and the base and was held in this position while axially extending external grooves forming internal ribs extending into the axial rooves of the base were forced into the metal cap.

The binding post of the said patent is very effective and efficient but in manufacture certain difiiculties have been encountered which militate somewhat against the speed and economy of production of the posts. For instance, the use of the base as the anvil against which the cap was compressed to form the axial ribs sometimes forced the cap out of round so that an extra operation was necessary to force the cap away from the ribs, back into cylindrical form. Of more importance was the fact that, as the wire-receiving apertures of the cap, the lower surfaces of which formed the upper end of the ribs, were arcuate, the actual contact with the upper surface of the peripheral groove was practically only by a pair of spaced points defining with an are a segment, so that in some cases a thin wire inserted through the wire-receiving apertures and the transverse bore when in registry, failed to establish a good tight contact because of disposition within the segment when the spring was allowed to force the cap upwardly to bring the upper end of the rib against the upper surface of the peripheral groove.

It is among the objects of this invention: to improve the art of binding posts; to improve the structure of the said Eby Patent No. 2,293,719; to make a binding post of extreme economy of construction and of utmost facility of assembly; to provide a binding post which will establish a firm electrical contact with any size of wire which it is designed to receive; and many other objects will become apparent as the description proceeds.

In the accompanying drawings, Fig. 1 represents an exploded elevation of one form of the present invention; Fig. 2 represents on a larger scale an elevation in part section of the assembled binding post; Fig. 3 represents an elevation of the mounted over the end binding post turned ninety degrees from the position shown in Fig. 2; Fig. 4 represents the elevation shown in Fig. 3, but with the parts compressed to expose the through bore ready to receive a conducting wire; and Fig. 5 represents the elevation shown in Fig. 4 with a conducting wire clamped in place; and Fig. 6 represents a fragmentary section of the With a wire gripped by the post.

Referring to the drawings, one form of the present invention consists of a five-part binding post including a base or anvil member Ill, a sleeve I I, a compression spring l2, a closure I3, and a threaded stem M. The base H] is generally cylindrical in shape and is formed with a peripheral groove l5, a through bore I6 in the plane of the groove l5, and two diametrically opposite axially disposed relatively narrow channels or grooves H. The groove I5 subdivides the base I!) into an upper head l8 and a lower skirt 20, which latter has its circumference interrupted by the aforesaid channels ll. The head I8 is internally cupped to form a seat 2| for one end of the compression spring l2, while its lower marginal edge 22 forms a narrow plane overhang above the groove l5. In other words, the radius of the groove I5 is such as to merge into the head appreciably within the diameter of the head I 8. This is important, as will later appear.

In order. to mount the binding post on a panel or other support, the stem I4 is threaded c0- axially into the base, and projects therefrom a sufiicient distance for the intended purpose.

For cooperation with the base Ill, the sleeve H has an internal diameter suitable for telescopic sliding co-action with the base In, and a length to receive the spring I2 and hold it under compression when the parts are operatively assembled. The head-engaging end Of the body portion of the sleeve II is preformed with two inwardly disposed diametrically opposite tongues or ribs 23, which are complemental in dimensions to the channels l1 and ride freely therein. Wire-receiving holes 24 are formed in the sleeve II and respectively intercept the inner ends of the tongues 23 to provide two transverse plane edges 25 as terminations respectivly of the tongues 23. Each hole 24 has two parallel sides 26 extending axially of the sleeve and merging into an are 21 spaced from the edge 25 a suflicient distance to permit the insertion of a conducting wire of the maximum diameter to be used with the binding post.

For closing the open end of the sleeve II, it is formed with a circumferential extension 28 of larger diameter than the body portion in order post illustrated in Fig, 2

to receive and seal a circumferential flange 30 on the closure 13. With such closure 13 in place, the end portion of the extension 28 is spun inwardly to encompass the flange 30 and thus mount the closure 13 in closing position.

In forming and assembling the parts, it is to be understood that the apertures or diametrically spaced wire-receiving holes 24 are initially D-shaped in outline, with the D on its side to have its straight edge formed by planar edge surface 25 at the bottom. The D-shaped holes are either made first or at the same time that axial ribs 23 are formed, with the lower straight edge 25 forming the upper terminus of ribs 23. The shell or sleeve H is open at both ends at the time of rib formation and the sleeve is assembled axially upwardly over the base with the ribs 23 in axial grooves or channels l1, after which the spring l2 and closure 13 are inserted and finally the upper edge of bead 28 is spun or swaged over the flange 3D to complete the assembly.

With the parts so assembled and with the closure l3 in place, the spring I2 is under compression and repels the base It! with respect to the closure 13 so that in normal position of the parts, with no conducting wire in place, the head l8 closes both of the sleeve holes 24 completely. It should pe noted that the base In is not expelled by the action of the spring 12, because the two plane edges 25 of the tongues 24 in a common plane parallel to anvil planar surface 22 of head 18 are in a path of movement which intersects marginal edge 22 of the head I8. Thus, at each side of the assembly there are two juxtaposed straight parallel edges resiliently forced together and which serve as jaws to grip any wire which traverses the holes 24 and passes through the bore l5. Thus, regardless of the diameter of any, even the most minute, wire designed to enter the bore l6, it will ,be gripped in a positive manner, between a flat end of the rib and a planar anvil surface on the base, in contrast to the loose or incomplete gripping which ordinarily occurs when a small wire is to be held by the binding posts of the prior art.

It will now beapparent that a complete unitary binding post has been devised wherein conductor wires of different diameters can be gripped with equal effectiveness and thereby the loose connections inherent in other binding posts are no longer present. Furthermore, the novel interengaging construction of the sleeve, closure and anvil, are so ingeniously correlated that the manufacturing steps have been reduced to a minimum with a consequent material saving in cost. Also, the provision of opposed fiat jaw surfaces as a gripping means instead of the jaws, one of which was arc-shaped heretofore in use, ensures not only a good contact-making gripping bite of every size of wire, but prevents slipping and loose connection with the held wire, while precluding shearing stresses common to other types of binding posts.

Having thus described my invention, I claim:

A binding post comprising a relatively stationary base having a transverse bore and a circumferentially extending groove substantially U shaped in cross section of a depth appreciably greater than its dimension axially of the base intersecting at least one end of the bore to form an upper substantially planar surface against which a wire in the bore can be forced for gripping purposes, said base having an axially extending surface groove extending from the end of the bore toward the lower end of the base, a movable sleeve mounted On the base and having a pair of aligned holes each sh'aped at the lower end in a transverse straight edge, said sleeve having an indented rib generally U-shaped in transverse section extending from the hole to the end of the sleeve, with the straight edge of the hole forming a substantially planar upper edge of the rib in position to engage axially the said substantially planar surface as an anvil, whereby any size of wire that can be disposed in the registering holes and bore is clamped between the planar upper end of the rib and the planar upper surface of the base, and means for urging the base and sleeve in such relative axial directions as to cause such clamping action.

BENJAMIN FOX.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,293,719 Eby Aug. 25, 1942 1,574,744 Aiken Mar. 2, 1926 FOREIGN PATENTS Number Country Date 140,047 Great Britain 1919 Certificate of Correction Patent No. 2,424,444. July 22, 1947.

BENJAMIN FOX It is hereby certified that the name of the assignee in the above numbered patent was erroneously Written and printed as Hugh H. Edy Whereas said name should have been Written and printed as Hugh H. Eby, as shown by the record of assignments in this Oflice; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 2nd. day of September, A. D. 1947.

LESLIE FRAZER,

Fir Ass ant Commis ioner of Pa ents,

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