US2968020A - Electrical connector - Google Patents

Description

Jan. 10, 1961 H. E. BARNHART 2,958,020

ELECTRICAL CONNECTOR I Filed Feb. 12, A1958 IN VEN TOR. Manor E. 3mm/H127' ELECTRICAL CONNECTOR Harry E. Bamhart, Sidney, N.Y., assignor to The Bendix Corporation, a corporation of Delaware Filed Feb. 12, 1958, Ser. No. 714,746

7 Claims. (Cl. 339-192) This invention relates to an electrical connector and more particularly to a separable electrical connector of such construction that it can successfully withstand high operating temperatures for long periods of time.

The invention has among its objects the provision of a novel electrical connector.

Another object of the invention lies in the provision of a novel sealed electrical connector adapted for incorporation in a sealed electrical conduit system.

Still another object of the invention is the provision of a novel electrical connector of such construction that it is able to operate successfully for long periods at high temperatures.

Yet another object is the provision of a compact rugged sealed electrical conduit system, and capable of successfully withstanding high operating temperatures for long periods of time.

A still further object is the provision of an electrical connector of the type above indicated of such construction that the assembly thereof is simple, and that no parts thereof are subjected to deleteriously high temperatures during the assembly and bonding of the parts thereof.

The above and further objects and novel features of the invention will more fully appear from the following description when the same is read in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration only and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

Fig. l is a view in longitudinal generally axial section through one part or element of a separable electrical connector made in accordance with the invention, certain parts being shown in elevation;

Fig. 2 is a view in longitudinal generally axial section through a second embodiment of a similar part or element of a second electrical connector made in accordance with the invention, certain parts being shown in elevation;

Fig. 3 is a somewhat schematic exploded view of the parts forming the sub-assembly of the connector element shown in Fig. l;

Fig. 4 is a View in longitudinal generally axial section through the completed sub-assembly, the parts of which are shown in Fig. 3, certain parts being shown in elevation; and

Fig. 5 is a somewhat schematic view taken generally in longitudinal axial section through a portion of a sealed States Patent conduit of which the connector element shown in Fig. 2

such as a jet or a ram-jet engine which becomes highly A ric heated when operating. Another typical use is in the circuit of a thermocouple, wherein the connector is placed close to a high temperature zone in which the thermocouple is located.

A successful electrical connector for such applications must maintain forceful and sure contact between the one or more connector pins and their sockets over an extended temperature range from atmospheric to highly elevated temperatures. In addition, the body or shell of the connector and the contact-bearing and electrically insulating inserts therein must be made of such materials as to withstand the high operating temperatures encountered, and to be of such construction as not to impose undue strains upon the parts as they are repeatedly rased from atmospheric to high operating temperatures and are cooled therefrom. Further, when the connector is of the sealed type adapted to be incorporated in a sealed electrical conduit system, the connector must incorporate therein a sealing means which remains effective throughout a large number of heating and cooling cycles.

Turning now to the drawing, two embodiments of connector elements made in accordance with the invention are shown therein, the two embodiments being essentially the same except for the construction of the outer shell or body thereof. The first embodiment of connector element is shown in Fig. l; the second embodiment of the connector element is shown in Figs. 2 and 5. Although, for simplicity of illustration, both embodiments of connector element shown are of the contact socketbearing type, it will be understood that with suitable modification of the shape of the electrically insulating inserts and of the passages therein the construction shown may be modified to be used as the connector pinbearing elements of the separable connector. It is also to be understood that, if desired, in certain embodiments one connector element may bear both contact sockets and contact pins.

The connector element shown in Fig. l is generally designated by the reference character 10. Element 10 includes an outer body or shell 12 which, in the described embodiment, is made of a suitable heat resistant metal such as Inconel or Hastelloy X. Shell 12 is of generally circular cylindrical contour, but has an enlarged seal-forming flange 13 intermediate its length. The forward end of body 12 is provided with threads 18 whereby it may be connected to a mating shell of the other element (not shown) of the separable connector of which element 10 is a part. The forward edge of body 12 is bevelled at 28 so as to form a seal with a complementary annular surface on such other connector element.

Body 12 has a longitudinally extending passage therethrough and an inwardly projecting annular ange 14 intermediate its length. The portion of the passage forwardly of flange 14 is generally of somewhat smaller diameter than that portion thereof rearwardly of the flange. Positioned within body 12 is a first or main ceramic insert 15 which positions the socket contacts 22 with respect to body 12 and insulates them therefrom. Insert 15 has a forward portion having a circular cylindrical outer surface accurately fitted within the forward portion of body 12 and an outwardly directed flange 17 which engages the rear surface of flange 14 on the body to prevent movement of insert 15 forwardly in the body 12. Positioned within the rear position of the passage through body 12 in abutting relationship with insert 1S is a second, disc-like, ceramic insulator 16 which forms a portion of the means for sealing the various conductors leading to the connector element 10. Interposed between insert 16 and the rearwardly extending axially flanged portion 21 of body 12 is a flexible, gas-impermeable diaphragm 19 having an inner smaller diametered end snugly telescoped over and sealed to the outer edge 20 of insert 16, a frusto-conical outer portion, and an outer, larger diametered circular cylindrical end snugly telescoped within flange 21r and sealed thereto.

Ceramic electrically insulating inserts 15 andv 16 may be made, for example, of alumina..v Diaphragml 19 may be made of flexible heat resistant metal such as heat resistant nickel-iron alloys. Further details of construction of the inner sub-assembly of connector element 1t) will appear in the following description of the method of making such sub-assembly, which is illustrated in' Figs. 3 and 4.

The ceramic insert 16 is molded to the shape shown with a number of holes 31 therethrough spaced over its area and corresponding to the number and location of the socket contacts to be provided in the connector element 1f?. The side walls of each of holes 31` are metallized, that is provided with a thin coating of metal,` in a conventional manner. Following this, a connecting element 24, shown in the form of a heat resistant metal tube, is inserted in each of holes 31 and after being properly located longitudinally thereof are brazed to the metallized side walls of the holes. The outer surface 2t? of ceramic insert 16 is also metallized and the inner smaller end of diaphragm 19 is telescoped thereinto and brazed to the metallized outer surface of member 16. Preferably this is done at the same time as members 24 are brazed within holes 31 of insert 16. A solder well member 25 is telescoped over the outer end of each of tubes 24 and a socket contact body 26 having a recess 32 at the rear end thereof is telescoped over the forward end of each of members 24. Preferably all members 241, 24, 25, and 26 are brazed at the same time,

The resulting sub-assembly, shown in Fig. 4 is then assembled with insert 15 so that the bodies 26 of the socket contacts extend within passages 23 through insert 15. The sub-assembly and insert 15 are then placed within body 12 by being slid in a direction from the rear to the front thereof. Following this the outer larger diametered end of diaphragm 19 is sealed to ange 21 of the body as by being edge-welded thereto at 33. For this operation a conventional Heliarc apparatus is suitable. The socket contact 22 shown is of the type disclosed and claimed in Barnhart application Serial No. 706,623, filed January 2, 1958, whichV not only affords excellent electrical connection throughout extended temperature ranges, but also facilitates assembly of connector element 10. Such socket contact has the body 26 thereof provided with a slot 29 in which there is positioned a bimetallic spring contact 27, the spring being held in place by a retaining sleeve 30. In making the assembly shown in Fig. l the bimetallic spring contact 27 and the retaining sleeve 30 preferably are assembled on body 26 prior to the telescoping of such body into the passages 23 in insert 15. In some instances, it may be desired to place the bimetallic spring within the slot 29 of each body 26, to assemble the sub-assembly of Fig. 4 with insert 15, and following the sealing of diaphragm 19 to flange 21 to place a retaining sleeve 30 over each body 26 and spring v27 by being inserted the sleeve through the open forward end of the holes 23 in insert 15.

The embodiment of connector element shown in Fig. 2 is designated generally by the reference character 11. The internal sub-assembly of such element is substantially identical with that of Figs. l, 3, and 4, and thus the parts thereof are designated by the same reference characters.

Connector element 11 differs from element 10 in the configuration of the main body or shell 34 thereof and in the manner in which such connector element is secured to its mating connector element (not shown). Body 34 has a forward circular cylindrical portion and a larger diametered rear portion 39, likewise circular cylindical.

4 The forward and rear outer surfaces of the shell are joined at 35 by an annular forwardly facing frustoconical seat and a rearwardly facing shoulder. A sleeved nut 36 rotatably mounted on the shell of element 11 serves to secure together the mating parts of the con nector. Nut 36 is provided with internal threads 38 adapted to engage threads on the other mating element, and with a flange 37 which engages the shoulder.

Fig. 5 illustrates an assembly of a sealed electrical conduit and the connector element 11 of Fig. 2. The conduit there shown, generally designated 42, is of the type disclosed and claimed in application Serial No. 687,416, filed October l, 1957. Such conduit includes an outer braided wire Sheath 46 an intermediate, gas-impermeable flexible sheet metal wall 46 having a plurality of longitudinally spaced convolutions therein, and an inner layer 49 of high electrical conductivity in order to supplement the radio-shielding effect of the outer shield 46. Conduit 42 is shown asl having its end sealed to a relatively rigid impermeable tubular adaptor member 51v by an annular seal generally designated 47. Such seal and the method of making it are the subject of application Serial No. 687,419, filed October l, 1957. Seal 47 includes a supplemental sleeve 50 which is welded to the end of conduit 42 and the end of adaptor 51 telescoped thereover by the weld 52.

In making the assembly shown in Fig. 5, the ends of the conductor wires 44 in conduit 42 are cut to the desired length and have the insulation removed from their ends as indicated. The assembly may be effected by initially telescoping adaptor member 51 over the end of conduit 42, the joint 47 having been made. Member 51 is slid backwardly along conduit 42 and the subassembly is then presented so that wires 44 may be secured to solder wells 25. Following this, member 51, 54 is slid to the left, the annular weld 55 between portion 39 of the shell and adaptor element 54 is made, and finally, member 51 is joined to conduit 42.

The assembly may also be effected, in some instances, in an alternative manner. It will be assumed, in such method, that the adaptor member 51 has been attached to the end of conduit 42 as above described, and that the forward end of adaptor 51 is either of the same diameter as sleeve 39 of element 11 or has had an adaptor member 54 integral therewith or secured thereto as by welding. The inner sub-assembly of element 11, similar to that shown in Fig. 4, is now placed at the mouth of member 54, the ends of wires 44 are placed inside of wells 25, and joined thereto. The open end of element 54 allows sufficient access for this to be accomplished. Following this the shell or body 34 is telescoped over the sub-assembly, and the rear end of such shell is secured to the forward edge of adaptor element 54 as by being edge-welded thereto at 55. To facilitate such latter operation, the rear edge of portion 39 of the flange is outwardly grooved at 40 (Fig. 2).

The resulting conduit and connector YVelement is effec tively sealed from the atmosphere. The flexible diaphragm 19 permits ceramic disc 16 to move with respect to shell 12 of the connector and to insert 15 as required by expansion and contraction of the parts without irnposing any undue strain thereon. The diaphragm 19 maintains the conduit sealed at all times, since ele'- ments 24 are sealed to insert 16, insert 16 is sealed to the diaphragm 19, the diaphragm is sealed to shell 12, and the shell is sealed to gasimpermeable element 45 of the conduit.

Although only a limited number of embodiments of the invention have been illustrated in the accompany# ing drawings and described in the foregoing specification, it is to be expressly understoodA that various changes, such as in the relative dimensions of the parts, materials used, and the like, as we ll as the suggested manner of use of the apparatus of the invention, may be made therein without departing from the Vspirit and scope of the invention as will now be apparent to those skilled in the art.

What is claimed is:

1. An electrical connector comprising an elongated metal shell, a gas impermeable electrically insulating ceramic insert positioned transversely within the shell with its periphery spaced inwardly from the inner wall of the shell, a passage through the insert directed longitudinally of the shell, an electrical conductor extending through the passage and sealed to the walls thereof, yieldable annular gas impermeable means interposed between and connected to the insert and the shell for supporting the insert in the shell and for effecting a seal between the insert and the shell, a second ceramic electrically insulating insert positioned within the shell inwardly of the first recited insert, said second insert being strong, rigid, and heat resistant, a further passage in the second insert aligned with the passage in the first recited insert and receiving the said electrical conductor, and means retaining the said second insert in the shell.

2. An electrical connector as defined in claim 1, wherein the inner end of the conductor is formed as a contact socket, and the second insert accurately receives and positions said socket.

3. An electrical connector as dened in claim 1, wherein the shell has an inwardly extending flange located axially inwardly of the shell with respect to the rst recited insert, the second insert has an outwardly directed flange overlying and located axially outwardly of the flange on the shell, and the broad transverse axially outer and inner surfaces of the second and first recited inserts, respectively, are substantially in contact.

4. An electrical connector as defined in claim 3, Wherein the inner end of the conductor is formed as a contact, and the second insert accurately receives and positions said contact.

5. An electrical connector as defined in claim 3, wherein the inner end of the conductor is formed as a contact socket, and the second insert accurately receives and positions said socket.

6. An electrical connector comprising an elongated strong, heat resistant, rigid shell, a gas impermeable electrically insulating ceramic insert positioned transversely within the shell with its periphery spaced inwardly from the inner wall of the shell, a passage through the insert directed longitudinally of the shell, an electrical conductor extending through the passage and sealed to the walls thereof, yieldable annular gas impermeable means interposed between and connected to the insert and the shell for supporting the insert in the shell and for effecting a seal between the insert and the shell, a second electrically insulating insert positioned within the shell inwardly of the rst recited insert, said second insert being strong, rigid, and heat resistant, and a further passage in the second insert aligned with the passage in the iirst recited insert and receiving the said electrical conductor, and means retaining the said second insert in the shell.

7. An electrical connector as defined in claim 6, wheren the means for retaining the said second insert in the shell comprises a radially inwardly directed member on the shell, the second insert being held between said member and the first insert.

References Cited in the le of this patent UNITED STATES PATENTS 1,281,917 Eby Oct. 15, 1918 2,194,886 Dallenbach Mar. 26, 1940 2,200,694 Gerecke et al. May 14, 1940 2,208,178 Berster July 16, 1940 2,642,474 Bower June 16, 1953 2,735,993 Humphrey Feb. 21, 1956 2,759,989 Anderson Aug. 21, 1956 FOREIGN PATENTS 952,421 France Ian. 12, 1945

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