US3398391A - Hermetically sealed connectors - Google Patents

Description

Au 20, 1963 A. R. BRISHKA HERMETIGALLY SEALED CONNECTORS Filed Aug. 10, 1967 Fl m .Itr 2 INVENTOR.

ALEXANDER R. BRISHKA JOHN P CHANDLER HIS ATTQRNEY United States Patent 0 3,398,391 HERMETICALLY SEALED CONNECTORS Alexander R. Brishka, 14 Sophia St., Mamaroneck, N.Y. 10543 Filed Aug. 10, 1967, Ser. No. 659,800 7 Claims. (Cl. 33994) ABSTRACT OF THE DISCLOSURE A hermetically sealed panel receptacle. comprising a tubular metallic body with means for attachment to the panel, a plastic insulator in interference fit in the body, an annular slot in the insulator receiving one end of the body, a center conductor through the insulator with a labyrinth seal between the insulator and the body and between the insulator and the conductor.

because of the difl'lculty in controlling the dielectric constant of the bead. It has also been found necessary in most cases to employ a second dielectric in addition to the glass or ceramic bead.

An important object of the invention is to provide a connector which retains its hermetic seal over a wide a range of temperatures and which permits the use of a unitary insulator employing only one type of plastic dielectric material and wherein it is not necessary to bond the insulator to the metallic surfaces.

The connector of the present invention has three basic parts: a tubular metallic body, a metallic center conductor, and an insulator formed of plastic material, such as PTFE.

The metallic body has a through bore of uniform diameter except for a section of reduced diameter at its upper end. On its exterior, the body has a threaded section at its upper end followed by an attaching flange and a lower end section of reduced diameter.

The insulator has an interference fit with the bore in the body and it also has a lower end section of enlarged diameter of slightly greater length than the reduced section of the body. This enlarged diameter insulator section has an annular slot extending downwardly from the shoulder formed by said enlarged section and as the insulator moves upwardly in the body, the reduced diameter lower end section of the latter passes into this annular slot in snug fit relation. Thus, the reduced section of the metallic body is tightly enclosed, internally and externally by the plastic insulator material which forms therewith a hermetic seal just as does the plastic insulator with the inner surface of the metallic body. To further insure the seal, a number of annular grip flanges are formed on the reduced diameter metallic body section which cut with the external insulator section, forming a labyrinth path. The central conductor which is forced through the insulator also has grip flanges between its ends which form, with the insulator, the same labyrinth path.

In the drawing:

FIG. 1 is a central longitudinal section taken through a panel receptacle of the present invention;

FIG. 2 is a plan view thereof.

The device of the present invention includes an insulator 10 of cylindrical shape which is of uniform diameter except that at its lower end it has an enlarged section 11 extending over about /3 its length and an annular slot 23 which extends over the major portion thereof. The insulator has an interference fit in a tubular body 12 having a through bore 13 of uniform diameter, a short section 14 of larger diameter at its upper end, and an external thread section 16 at the same end. Near the lower end the body has an external annular flange 18 with a circular recess 19 on its lower surface.

Between this flange and the lower end 20 the body has a section 21 of reduced diameter and, hence, wall thickness and formed on its outer surface with annular grip flanges 22 which slope upwardly away from said lower end. The cross sectional width of annular slot 28 is about the same as the wall thickness of reduced section 21 which it receives in snug fit relation with the grip flanges fitting into the plastic body, thus forming a labyrinth path.

The upper end 23 of the cylindrical insulator is forcefitted into the tubular body from the lower end of said body and when the lower end 20 of the body reaches the upper end 24 of the enlarged insulator section it readily passes into slot 23 and forms a separate annular wall lying outside of and in close contact with the reduced body section 21.

A central contact 28 is now pressed into the insulator, the contact having a plurality of annular gripping flanges 29 between its ends. The upper end has an opening 30' to receive a male contact in force fit relation and the lower end has a reduced contact section 31.

The insulator may have a small predrilled hole or the metallic contact may simply be forced through the solid body. The gripping flanges, in addition to firmly enclosing the contact in the insulator body, also forms an effective hermetic seal with a labyrinth path.

The flange or base 18 has corner openings 34 to enable it to be mounted as by means of bolts to a panel or chassis shown in broken lines at 36. A resilient O ring 37 is placed within recess 19 and is compressed therein against the panel, thus further insuring a hermetic seal.

After installation of the assembly, when there is an increase in temperature, the insulator, whose coefi'icient of expansion is greater than that of the metallic components, expands. The greater part of this expansion, occurs in a longitudinal direction, since the material has no other means of expansion. Any expansion in length applies a force against the gripping flanges of the contact thus maintaining an effective seal. When a decrease in temperature occurs, the insulator contracts, applying an inward radial force on the contact and the enlarged section v11 of the insulator lying outside reduced body section 21 contracts around this body section. It is apparent then, whether the insulator expands or contracts, the seal is always maintained.

The use of the terms upper and lower in the specification and in the appended claims are employed only for the sake of consistency with the figures of the drawing. While the connectors of the present invention will frequently be installed in horizontal panels, they usually will have a wide use in vertical panels, all as Will be cleary understood.

While there have been described herein what are at present considered preferred embodiments of the invention, it will be obvious to those skilled in the art that many modifications and changes may be made therein without departing from the essence of the invention. It is, therefore, to be understood that the exemplary embodiments are illustrative and not restrictive of the invention,

the scope of which is defined in the appended claims, and that all modifications that come within the meaning and range of equivalency of the claims are intended to be included therein.

.The embodiments of the invention in which the exclusive property of privilege is claimed are defined as follows:

1. A receptacle for mounting on a panel or chassis and including a metallic body formed with a through bore, a section of reduced diameter at its lower end and provided with an external annular grip flange, and a flange above the reduced section for attachment to the panel, an insulator of plastic material received in interference fit relation in the body and provided with an enlarged section at its lower end, forming a shoulder, and having an annular channel therein extending downwardly from said shoulder, which receives said reduced body section in snug fit relation, and a metallic conductor passing through the insulator in force fit relation, said grip flange forming, with the insulator lying outside the same, a labyrinth seal, said flange adapted to be secured to said panel.

2. The structure described in claim 1 wherein the annular slot in the enlarged insulator section is of substantially the depth as the height of the reduced diameter body section received therein.

3. The structure described in claim 1 wherein the metallic conductor has an external grip flange to form a labyrinth seal with the insulator.

4. The structure described in claim 1 wherein the flange has an annular recess in its lower face surrounding the reduced diameter body section to receive a sealing gasket when the flange is mounted on the panel.

5. The structure described in claim 1 wherein the metallic conductor has an opening at one end to receive a male contact.

6. The structure described in claim 1 wherein the metallic body has an external threaded section.

7. The structure described in claim 1 wherein the insulator is formed from PTFE.

References Cited UNITED STATES PATENTS 2,552,414 5/1951 Eriksen et a1. 339178 X 2,881,406 5/1959 Arson 33994 X 2,906,986 9/1959 Schaefer 339-60 3,022,484 2/1962 Thompson 339-94 X 3,290,639 12/1966 Driemeyer 339-218 X 3,292,132 12/1966 Murphy 339221 X RICHARD E. MOORE, Primary Exammer.

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