US3221292A

US3221292A - Electrical connector

Info

Publication number: US3221292A
Application number: US145958A
Authority: US
Inventors: George J Swanson; Harry E Barnhart
Original assignee: Bendix Corp
Current assignee: Bendix Corp
Priority date: 1961-10-18
Filing date: 1961-10-18
Publication date: 1965-11-30
Anticipated expiration: 1982-11-30
Also published as: DE1440794A1; GB995022A; ES281639A1; DE1440794B2; GB995021A

Description

0 1965 G. J. SWANSON ETAL 3,221,292

ELECTRICAL CONNECTOR Filed Oct. 18, 1961 4 Sheets-Sheet 2 INVN RS BY GEORGE J. SWANSON HARRY E. BARNHART Nov. 30, 1965 G. J. SWANSON ETAL 3,221,292

ELECTRICAL CONNECTOR Filed Oct. 18, 1961 4 Sheets-Sheet 3 E %ME!QQLQE% VENTORS GEOR J. SWAN q- B HARR Y Y E BARN T wfizmwe ATTO NEYS Nov. 30, 1965 J. SWANSON ETAL 3,221,292

ELECTRICAL CONNECTOR Filed Oct. 18, 1961 4 Sheets-Sheet 4 M W F I09 "\k' /4 2 m/fifi/ INVENTORS GEORGE J. SWANSON BY HARRY E. BARNHART ATTOR YS United States Patent 0 3,221,292 ELECTI-KECAL CGNNECTQR George J. Swanson and Harry E. Barnhart, Sidney, N.Y., assignors to The Bendix Corporation, Sidney, N.Y., a corporation of Delaware Filed Get. 155, 1961, Ser. No. 145,958 6 Claims. (Cl. 339217) This invention relates to electrical connectors, and particularly relates to electrical connectors with selectively removable contacts.

The invention has among its objects the provision of a novel electrical connector with removable contacts, the construction of the connector being such as to improve the security of contact retention.

A further object of the invention lies in the provision of an electrical connector of the indicated type, the connector being of such construction as markedly to lessen the time required for the assembly of its parts.

Still a further object of the invention lies in the provision of an electrical connector with removable contacts, the connector assuring quick replacement by the use of simple tools of contacts as required, as for changes in circuitry.

Another object of the invention resides in the provision of an electrical connector of the indicated type wherein contact insertion and withdrawal does not aifect the electrical or mechanical characteristics of the connector assembly.

Other objects of the invention lie in the provision of connectors embodying the contact-securing means of the invention which will mate with similar connectors now in use but not employing such means, and in the provision of contact-securing means which may be employed with contacts which are secured to wires or cables by either a soldered or a crimped joint.

Yet another object of the invention lies in the provision of an improved grommet of novel construction which provides for the more secure sealing of the conductors to the grommet of the connector part.

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. 1 is a view in longitudinal axial section through two aligned confronting parts of a separable electrical connector made in accordance with a preferred embodiment of the present invention, the two connector parts being shown in position to be coupled together by axial movement toward each other followed by manipulation of the locking means, some of the parts being shown in side elevation;

FIG. 2 is a view in end elevation of the connector part shown at the left in FIG. 1, the view being taken in the direction from right to left in FIG. 1;

FIG. 3 is a view in end elevation of the connector part shown at the right in FIG. 1, the view being taken in the direction from left to right in FIG. 1;

FIG. 4 is an enlarged fragmentary view of one of the socket contacts, which is shown in phantom lines, and its retaining bushing, the contact and bushing being turned 180 from the position thereof shown in FIG. 1, portions of the composite insert mounting the contact and contact-retaining bushing being fragmentarily shown in section, the section being taken along the line 44 of FIG. 7;

3,221,292 Patented Nov. 30, 1965 FIG. 5 is a view in cross section taken axially of the contact-retaining bushing of FIG. 4, the socket contact retained by the bushing being shown in side elevation, portions of the composite insert of the connector being fragmentarily shown, the section being taken along the line 5-5 of FIG. 7;

FIG. 6 is a view in section generally similar to FIG. 5, the contact-retaining bushing being shown in the act of being spread by a contact withdrawal tool preparatory to the withdrawal of the contact from the connector insert;

FIG. 7 is a view in transverse section through the socket contact and a portion of the connector insert, the section being taken along the line '77 of FIG. 5;

FIG. 8 is a view in transverse section through the socket contact, a portion of the connector insert, and a part of the withdrawal tool, the figures showing the fingers of the contact-retaining bushing in spread condition, the section being taken along the line 88 of FIG. 6;

FIG. 9 is a somewhat schematic view partially in vertical section and partially in elevation of apparatus employed to assemble the contact-retaining bushings in the intermediate portion of the connector insert;

FIG. 10 is a view in longitudinal section through the insert of connector part 11, the section being taken generally along the axis of a contact-retaining bushing in the insert, the contact pin retained by the bushing being shown in elevation;

FIG. 11 is a view in section somewhat similar to that of FIG. 10 but showing the application of a withdrawal tool to the contact-retaining bushing and the contact partially withdrawn from the insert;

FIG. 12 is a view partially in axial section and partially in elevation of a contact-withdrawing tool such as that fragmentarily shown in FIG. 11;

FIG. 13 is a view in end elevation of a grommet employed with the insert of a connector part made in accordance with the invention, the view being taken in the direction from the bottom to the top in FIG. 14; and

FIG. 14 is a view in axial section through the grommet of FIG. 13, the section being taken along the line 14-14 of FIG. 13.

The electrical connector of the present invention, and the contact-securing bushing thereof, are particularly advantageous when they are employed with contacts which are connected to their respective conductors, such as wires, by being crimped thereto rather than soldered. As above indicated, however, the connector and contact-retaining means of the inevntion may also be employed, if desired, with contacts which are soldered to their respective wires. The electrical connector of the present invention is of such construction that, after a joint has been made between the end of a wire and a contact, the contact and wire may then be readily mounted into a previously assembled connector part, including a shell having a contact-retaining insert therein, such insert having contact-retaining bushings in accordance with the invention. The contact and the bushing of the invention have interfitt-ing formations thereon so constructed and arranged that the contact may be thrust into its fully inserted operative position by essentially straight line axial movement thereof, the contact being securely held in such position despite repeated operations of engagement with and disengagement from a mating contact. The construction of the insert and contact-retaining formations is preferably such that, when necessary, the contact may be removed from the connector part by an operation which is the reverse of the assembly operation. As a result of such preferred construction, errors in circuit connection may be readily corrected without injury to the contact or to the locating and retaining insert and bushing of the connector part.

Turning now to the drawings, there is shown in FIG. 1 a

separable electrical connector of the multi-contact type, both halves of such connector being made in accordance with the present invention. The connector half or part at the left, designated 11 in the embodiment shown, is adapted to support and retain a plurality of pin contacts, generally designated 25. The connector part shown at the right in FIG. .l and generally designated 12, is adapted to support and retain a plurality of socket contacts which are generally designated 27. Connector parts 11 and 12 are shown somewhat separated but aligned so that the respective socket and pin contacts carried thereby will be placed in mating relationship when connector parts 11 and 12 are advanced into operative engagement. In the embodiments shown, the shells or housings of the connector parts, and the means for holding the connector parts in operative engagement, are generally similar to those disclosed and claimed in Hennessey et al. .Patent No. 2,984,-

Briefly, the connector part 11 has a tubular shell 14 which is adapted for mating with the forward portion of the shell 15 of connector part 12. A rotatable sleeve 16 mounted on shell 14 carries a plurality of bayonet grooves 17 which are adapted to receive the bayonet pins 19 on the forward or hood portion of shell 15. An annular leaf spring 20 of wave form resilently thrusts the two connector parts together when the bayonet connection is tightened. A sleeve 21 screwed onto housing 14 both prevents sleeve 16 from rearward escape and retains the grommet portion of the insert in shell 14. A plurality of splines, one of which is shown at 22, are receivable in complementary grooves, one of which is shown at 24, to orient the connector parts and guide them with respect to each other. A sleeve 23 threadedly connected to shell 15 serves to retain the grommet portion of the insert of connector part 12.

The contacts mounted in connector part 11, which are generally designated 25, have forwardly projecting pin portions 26. Pin portions 26 are designed selectively to be received within socket contacts in connector part 12, the socket contacts being generally designated 27, the socket portions of such contacts being designated 29. In connector part 11 there is mounted a composite insert 30 in shell 14, such insert having a first or forward portion 31 made of electrically insulating rubber or rubber-like material of intermediate durometer, an intermediate contact-retaining portion 32, and a rear grommet portion 34. The insert 35 in connector part 12 is of a similar composite construction, there being a forward insert portion 36, an intermediate contact-retaining portion 37, and a rear or grommet portion 39. The forward, intermediate, and rear portions of both composite inserts are adhesively secured together in the fully assembled connector parts, the parts of the inserts being cemented together at their engaging faces after the contact-retaining bushings have been assembled in the intermediate portions of the insert in a manner to be described. The

intermediate portions

32 and 37 of the composite inserts are made of strong, tough electrically insulating material such as nylon or Teflon.

l The pin contacts 25 and the socket contacts 27 in the connector parts shown are both of the type in which the conductor or wire is secured to the contact by a crianped connection. The constructions of both such contacts rearwardly of the pins and the sockets thereof are the same so that such contacts may be used interchangeably with the contact-retaining bushings to be described. Socket contact 27 has a ferrule 40 which is designed to receive the bared end of a Wire 42 and to be crimped to make firm connection therewith. The indentations formed in the wall of the ferrule by such crimping operation are shown at 45. Pin contact 25 has a similar ferrule designated 4th. Rearwardly of ferrule 40 socket contact 27 has a sleeve 41 of larger diameter than the ferrule, the sleeve being adapted to receive the forward end of the insulation 44 of the wire therewithin. Pin contact 25 has a similar sleeve 41' rearwardly of ferrule 4d.

The intermediate member of each of

composite inserts

30 and 35 and contact-receiving bushings mounted in such intermediate member constitute the means whereby the respective contacts are retained from. axial movement. In FIGS. 4, 5, and 6 a portion of such intermediate insert member 37 of connector part 12 is shown with the contact-retaining bushing associated therewith. Member 37 is provided with a plurality of holes therethrough, the hole shown in FIGS. 4, 5, and 6 being designated 46. At the forward end of hole 46 there is provided a shallow radially inwardly directed flange 47 having a sharp forward edge 49 and a somewhat rounded rear edge 50. The main peripheral extent of flange 47 is circular cylindrical. Firmly seated within the forward end of hole 46 in member 37 is a contact-retaining bushing generally designated 51. In the embodiment shown, bushing 51 is integral, and has been machined from solid bar stock. The bushing is made of strong springy material such as a berylliumcopper alloy. Bushing 51 has a rear sleeve portion 52, the outer periphery of which strongly engages the periphery of flange 47. Bushing 51 is retained from axial movement with respect to member 37 by means of a forward annular flange 54 which engages the forward face of member 37 and a rear flange 55 which engages the rounded edge 50 of flange 47.

The forward end of bushing 51 is provided with a plurality of contact-retaining fingers 56 which are formed by a plurality of slots 57 angularly spaced about the axis of the bushing. In the embodiment shown there are four such equally spaced slots and four identical fingers. It is to be understood that the angular spacing of the slots and the number thereof may be varied; thus, for example, there may be, if desired, six slots in the forward end of the bushing dividing it into six similar fingers. The rear end portions 59 of each finger, which extend forwardly from the flange 54, are of radially reduced section so that they may be flexed during engagement of a contact therewith and disengagement of a contact therefrom. For clarity in FIG. 4 an exaggerated annular space is illustrated between portion 59 of the bushing and insert portion 36. The forward end 60 of each finger is of relatively thick section and functions as a latch. The forward edge of each finger is bevelled at 61, the radially inner end of the bevel leading inwardly to an axially short surface 62 which is a part of a circular cylinder. At the rear end of surface 62 there is a shoulder 64 which, in the embodiment shown, is reentrant angled. Outwardly of shoulder 64 there is a short surface 66 in the form of a part of a circular cylinder. Rearwardly of surface 66 there is a sloping surface 67, in the form of a portion of a cone, which connects surface 66 with the inner surface of the sleeve 52 and the root 59 of the finger.

In FIG. 5 there is illustrated the relationship between a socket contact 29, the member 37 of the composite insert of the connector part and the contact-retaining bushing 51 which such parts have when fully assembled in operative relationship. A similar assembly incorporating a

contact pin

25, 26 instead of a socket body is shown in FIG. 10. Since the relationship of the parts is similar in each case, a detailed description of the assembly is confined to that of FIG. 5. The forward insert portion 36 has a passage 69 therein which receives the forward part of the contact-retaining bushing, as shown, Coaxial with passage 69 in insert portion 36 is a further passage 70 of somewhat smaller diameter than passage 69. The body of the socket contact 29 is disposed within passage 70 with its surface spaced somewhat from the wall of passage 70. The circular cylindrical portion 7-1 of the body of the socket contact lies within and substantially accurately interfits with the portion 52 of the bushing 51. Forwardly of surface 71 the body of the socket contact is frusto-conical at portion 72, the forward smaller diameter end of portion 72 being joined to the body of the contact containing the socket by a sharply angled annular shoulder 74. When the parts are disposed as shown in FIG. 5, the shoulder 64 of each of fingers 56 is in substantial engagement with shoulder 74 of the socket contact, and flange 48 on the socket contact, which has an effective diameter greater than the inner diameter of portion 52 of the bushing, lies slightly to the rear of flange 55 on the bushing. The socket contact is thus held against any appreciable axial movement in either a forward or rearward direction.

The socket contact may, however, be readily removed from the connector part when desired. Such removal is effected by means of a withdrawal tool having a thin elongated sleeve 75 with an inner diameter such that it readily receives the socket contact therewithin and an outer diameter such that it is slidably received within the passage 70 in insert part 36. The forward end 82 of sleeve 75 is bevelled in the same direction as surfaces 61 of fingers 60, so that as the sleeve 75 is thrust in the direction from right to left, as shown in FIG. 6, the forward end of the sleeve cams the fingers 60 outwardly so as to withdraw the inner edges of shoulders 64 radially outwardly beyond the annular shoulder 74 on the body of the contact. During such action the passage 69 in insert part 36 is deformed in an outward position, as shown at 69, to allow such retraction of the fingers from the contact. After the fingers have been thus retracted from the contact, the contact may be thrust to the left and thus rearwardly out of the insert 37 by means of a rod 77 which is guided within the sleeve 75 and which has a diameter substantially the same as that of socket contact 29 whereby it abuts the forward end of the socket contact.

The sleeve 75 and rod 77 may be parts of a withdrawal tool generally designated 79. As shown in FIG. 12, withdrawal tool 79 has a handle 80 integral with sleeve 75. Positioned axially within handle 80 and sleeve 75 is the withdrawal rod 77 which, as above explained, has a diameter generally the same as that of the socket body 29. Rod 77 has a further handle 85 on its outer end, by means of which the rod 77 may be conveniently reciprocated relative to sleeve 75.

The contact pin 25 is generally similarly unlocked and withdrawn from the composite insert 30 of connector part 11. Such operation may be carried out by use of the above-described withdrawal tool 79. The sleeve 75 is inserted in the passage 68 of insert 30 as shown in FIG. 11, the bevelled forward end of sleeve 75 camming the spring fingers of the contact-retaining bushing outwardly, as shown. The rod 77 is now advanced so that its forward end engages the outer end of contact pin 26. Preferably, the end of rod 77 is provided with a shallow central bore 73 which receives the outer end of pin 26. When rod 77 is thrust to the left (FIG. it pushes the contact out of the insert-retaining bushing, whereby the contact may be completely removed from the insert of connector part 11.

The pin and socket contacts may be inserted within the composite inserts 30 and 35, respectively, in a number of acceptable ways. The contacts may be thus inserted, for example, by a pliers-like tool such as that disclosed in Swanson application Serial No. 808,611, filed April 24, 1959 and now Patent No. 3,125,395. Alternatively, the inserting tool may be in the form of a longitundinal sectioned tube which is disposed to the rear of and coaxially of the contact so as to receive the conductor or wire within it and to abut the sleeve 41 or 41' at the rear end of the contact. When the contact and tool have been thus assembled, the contact is advanced axially into its passage in the composite insert and is thrust home within the contact-receiving bushing.

The contact-retaining bushing 51 may be mounted within the

intermediate insert portions

32 or 37 in the manner somewhat schematically shown in FIG. 9. In such figure a fragment of insert portion 37 is shown supported upon a fixed press platen 86 having a hole 87 therein aligned with the passage 46 in insert portion 37. The annular flange 47 on insert portion 37 is shown disposed remote from platen 86. A bushing 51 is mounted upon a bushing inserting tool 89 with the sleeve portion 52 of the bushing disposed closer to the insert portion 37. Tool 89 has a forward frusto-conical end 90; a short circular cylindrical portion 91, having generally the same diameter as flange 55 of bushing 51; a second smaller circular cylindrical portion 92; and a third, still smaller, elongated shank portion 94. Portion 92 of the tool accurately fits within the sleeve 52 of the bushing.

After the bushing has been thus assembled upon tool 89, and the tool has been presented to the insert portion 37 in the manner shown, the further end of shank 94 is pressed toward the insert portion by a press plunger 95. It will be obvious that, as the plunger 95 travels toward the platen 86 the flange 47 of the insert portion is progressively stretched and widened so that the flange 55 of the bushing sleeve may be inserted therein. The press plunger thrusts the bushing into the sleeve until the flange 47 has been received between the

flanges

54 and 55 on the bushing. The inner diameter of flange 47 and the outer diameter of the portion of bushing 51 between

flanges

54 and 55 is preferably such that after the bushing has been thus assembled in insert portion 37 there is at least some degree of compression between the peripheral surfaces of the flange 47 and of the sleeve 52.

In FIGS. 13 and 14 there is shown a novel grommet in accordance with the invention, the grommet specifically being that designated 39 and employed in the connector part 12 shown in FIG. 1. It is to be understood that such grommet is generally the same as the grommet designated 34 employed with the connector part 11 shown in FIG. 1. Grommet 39 is shown in FIG. 14 as having 55 passages extending therethrough and distributed over its area. Each of such passages is of such construction as to provide two axially spaced webs which sealingly cooperate with the conductor or wire which extends therethrough and is connected to the respective contact in the connector part. In the specific grommet shown, 27 of such passages, designated 97, are of a first type, herein designated type A, and 28 of such passages, designated 96, are of a second type, herein designated type B. The passages 96 have an elongated circular cylindrical portion 99 of the passage, portion 99 having at its outer end a first or inner web having a constricted throat portion 100 joined to passage 99 by a frusto-conical transition zone 101. Axially rearwardly of throat 100 the passage flares to an enlarged circular cylindrical zone 102 from which it tapers rearwardly in a frusto-conical zone 103 to a second, outer web portion 104.

The passages 97 have an elongated circular cylindrical inner portion 106 which is somewhat longer than portion 99 of passages 96. From the outer terminus 110 of portion 106 the passage converges axially rearwardly in a frusto-conical zone 109 to a first or inner web having a throat portion 107. Axially outwardly from throat 107 the passage is flared to join with a short circular cylindrical zone 112. Outwardly of zone 112 the passage has a second or outer web 114 which is joined to portion 112 by the frusto-conical portion 113.

The distribution of passages 97 (type A) and 96 (type B) over the area of the grommet is shown more clearly in FIG. 13. As there shown, there is one central passage. The remainder of the passages in the grommet, with the exception of those near its outer edge, are disposed at the apices and/or along the sides of three concentric similar hexagonal figures. The openings through the grommet adjacent its outer edge are disposed generally along a circle parallel to such edge. In each of the three hexagonal figures openings of type A alternate with those of type B. In the outer circular arrangement of openings, openings of type A also alternate with those of type B. Throughout a predominant part of the grommet, diametral lines through aligned passages will have passages of type A alternating with those of type B. Also, with a few exceptions, any opening of type A will be surrounded by openings of type B and conversely, any opening of type B will be surrounded by openings of type A.

As a result of such construction, it will be seen that where openings of type A and those of type B adjoin each other there is formed a dividing and insulating wall between them in the grommet which is of undu-latory shape and which provides a wall of the maximum thickness consistent with the provision of the two sealing webs at each passage in the grommet.

The axially spaced webs or constrictions in the two types of passages in the grommet are of such construction as to allow the contact to pass therethrough in either the forward or rearward direct-ion. At the same time, because there are two constrictions in each passage and because of the undulatory shape of wall presented between a predominant number of the passages and the other passages adjacent thereto, a secure sealing is attained between the grommet and the wire leading to each of the contacts positioned in the insert.

The contact-retaining bushing 51 may be formed in a number of ways. It is preferred, however, that it be formed by machining from a solid piece of bar stock. In order that the contact may be securely held against rearward movement when it is positioned with respect to the bushing in the manner shown in FIG. 4, it is highly desirable that the surface 64 of the latch member shall be disposed with respect to the axis of the bushing at an angle which is at least 90, such angle being measured between surface 64 and the portion of the axis of the bushing forwardly of the intersection of the projection of shoulder 64 with such axis. In the embodiment shown, such angle somewhat exceeds 90, having been deliberately machined to that angle to insure that the latch members shall have sharp forward edges. In some instances it is desirable that, after the forward portion of the bushing has been rough machined and the slots 57 have been formed therein the resulting fingers 56 be flared outwardly to an appreciable extent before the

surfaces

62 and 64 are machined thereon. Such procedure makes it easier to assure that the edge of the latch member between

surfaces

64 and 66 will be sharp and that the surface 64 will lie at the desired angle in the finished bushing. Following such machining step, and either before or after the other surfaces of the bushing have been finished machined, the spring fingers 56 are bent to place them stably in the position shown in FIGS. 4 and 5.

Although only one embodiment of the invention has been illustrated in the accompanying drawings and described in the foregoing specification, it is to be especially understood that various changes, such as in the relative dimensions of the parts, materials used, and the like, as well as the suggested manner of use of the apparatus of the invention, may be made therein without departing from the spirit 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 a tubular housing, a composite electrically insulating insert member secured within said housing, said insert member comprising a forward elastomeric portion, an intermediate contactretaining plate made of relatively stifi but elastically deformable material, and a rear contact-sealing grommet, said insert member having a plurality of passages longitudinally therethrough, said passages being spaced over the transverse area of the insert member, and an elongated contact in each passage having a substantial part of its length located within its respective passage, contactretaining means affixed to the plate at each of the passages, each of said contact-retaining means having at least one latch member resiliently yieldable in a radially outwardly direction, each of said contacts having rear and forward axially spaced formations thereon cooperating with portions of its contact-retaining means including the latch member thereon to retain the contact from appreciable longitudinal movement relative to the insert member during normal connecting and disconnecting operations, the forward formation on the contact and the latch member being such as to allow such forward formation to be thrust past the latch member in the forward direction by deflecting the latch member radially outwardly as the forward formation on the contact travels therepast, the grommet being made of relatively soft elastomeric material, the portion of each of the contact-receiving passages in the grommet presenting two axially spaced constrictions each having an inner diameter substantially less than the diameter of the contact, the grommet being yieldable at said constrictions to allow the passage of the contact both forwardly and rearwardly therethrough, the passages through the grommet being of two types, the constrictions in one type of passage being substantially out of transverse alignment with the constrictions in the other type of passage, throughout a predominant part of the grommet a passage of one type being located adjacent to passages of the other type.

2. A grommet for sealing a plurality of wires passing therethrough in generally parallel relationship, the grommet being made of relatively soft elastomeric material, the grommet having a plurality of wire-receiving passages longitudinally therethrough, said passages being spaced over the area of the grommet, the grommet presenting two axially spaced constrictions in each passage therethrough, the passages through the grommet being of two types, the constrictions in one type of passage being substantially out of transverse alignment with the constrictions in the other type of passage, throughout a predominant part of the grommet a passage of one type being located adjacent to passages of the other type.

3. An electrical connector comprising a tubular housing, an electrically insulating insert member secured within said housing, said insert member comprising a forward elastomeric portion and a contact-retaining plate made of substantially rigid but elastically deformable material disposed rearwardly of said forward portion, said insert member having at least one passage longitudinally therethrough, and an elongated contact having a substantial part of its length located within said passage, contactretaining means aflixed to the plate at the passage, said contact-retaining means being in the form of a bushing having a peripherally continuous sleeve portion surrounding and guidingly engaging an annular zone of the contact intermediate the length thereof, said sleeve portion of the bushing being positioned within and compressively engaged by an annular zone of the wall of the passage through the plate, and wherein the sleeve portion of the bushing has radially outwardly directed flanges adjacent its opposite ends, the Wall of the passage through the plate having a radially inwardly directed flange thereon, said flange being of substantially less axial thickness than the thickness of the plate, the flanges on the sleeve portion of the bushing overlying and snugly engaging the side edges of the flange on the Wall of the passage through the plate, whereby the bushing as a whole is positively locked independently of said forward portion against any movement relative to the plate; said contact-retaining means having at least one latch member resiliently yieldable in a radially outwardly direction, said contact having rear and forward axially spaced formations thereon cooperating with portions of the contact-retaining means including the latch member thereon to retain the contact from appreciable longitudinal movement relative to the insert during normal connecting and disconnecting operations, the forward formation on the contact and the latch member being such as to allow such forward formation to be thrust past the latch member in the forward direction by deflecting the latch member radially outwardly as the forward formation on the contact travels therepast and being adapted to prevent rearward movement of the contact through the bushing when the latch member is in relaxed position and wherein the rear portion of the passage through the plate, rearwardly of the rear flange on the sleeve portion of the bushing, is in the form of a circular cylindrical bore of substantial length, and said rear formations comprising a radially outwardly directed shoulder on the contact lying within the rear portion of the passage and closely confronting the rear end of the rear flange on the sleeve portion of the bushing, said shoulder on the contact having a diameter appreciably greater than the diameter of the passage through the sleeve portion of the bushing whereby the contact is retained against substantial axial movement in either direction with respect to the bushing.

4. An electrical connector comprising an elongated contact, means for supporting and removably retaining said contact, said means including a substantially rigid disc-like member having a passage therethrough, and a spring metal bushing for slidably receiving said contact and for removably locking the same against longitudinal movement relative to said member, said bushing having a cylindrical sleeve portion and a plurality of circumferentially arranged spring fingers extending forwardly from the edge of said sleeve portion, said sleeve portion having an external annular groove closely engaged by an internal rib in said passage to hold the bushing against movement relative to said member and each of said fingers having a radially inwardly extending latching portion for engaging a rearwardly facing shoulder on said contact to hold the latter against rearward movement, said latching portion having a tapered forwardly facing surface which extends rearwardly and radially outwardly to provide a sharp edge for engagement with said shoulder on the contact and said shoulder being tapered rearwardly and radially inwardly from the periphery of the contact.

5. An electrical connector comprising a composite body having a bore extending therethrough, said body comprising a forward portion of resilient rubber-like material, an intermediate disc-like plate of material which is substantially rigid but slightly resiliently yieldable to substantial radially directed force in said bore therethrough and a relatively soft rubber-like grommet, a metal contact retaining member entirely within the bore and fixedly located therein by interlocking engagement with said plate, said member including a sleeve-like portion defining a contact-receiving opening and having a series of spring fingers extending therefrom, said spring fingers having outer surfaces which are in engagement at the outer ends thereof with the surface defining the bore in said forward portion of the body and having interior sur faces including portions tapering inwardly as they extend away from the sleeve-like portion and terminating at shoulders spaced inwardly from the outer ends of said fingers, and an electrical contact removably mounted in said bore, said contact having an end extending through the contact-retaining member in the bore and having a portion of reduced section intermediate its ends, said reduced portion having shoulders at opposite ends thereof, one of which engages with the sleeve-like portion of the retaining member and the other of which engages with the shoulders on said spring fingers, whereby the contact is held against axial movement relative to said body and wherein the surfaces of said shoulders on the fingers are tapered rearwardly and outwardly to provide a sharp edge engagement with said other shoulder on the contact.

6. An electrical connector as defined in claim 5, wherein said other shoulder on the contact tapers rearwardly and inwardly relative to the axis of the contact.

References Cited by the Examiner UNITED STATES PATENTS 2,327,605 8/ 1943 Ryder. 2,419,018 4/1947 Gudie 339-217 X 2,563,712 8/1951 Frei et a1. 339-60 2,563,713 8/1951 Frei et a1. 339-63 2,563,762 8/1951 Uline et a1. 339-60 2,881,406 4/1959 Arson 339-102 X 2,984,811 5/1961 Hennessey et al. 339- 2,999,221 9/1961 Ellis et a1 339-217 X 3,028,574 4/ 1962 DiMonte 339-61 FOREIGN PATENTS 1,246,003 10/ 1960 France.

262,532 12/ 1926 Great Britain.

JOSEPH D. SEERS, Primary Examiner.

PATRICK A. CLIFFORD, Examiner.

Claims

2. A GROMMET FOR SEALING A PLURALITY OF WIRES PASSING THERETHROUGH IN GENERALLY PARALLEL RELATIONSHIP, THE GROMMET BEING MADE OF RELATIVELY SOFT ELASTOMERIC MATERIAL, THE GORMMET HAVING A PLURALITY OF WIRE-RECEIVING PASSAGES LONGITUDINALLY THERETHROUGH, SAIS PASSAGES BEING SPACED OVER THE AREA OF THE GROMMET, THE GROMMET PRESENTING TWO AXIALLY SPACED CONSTRICTIONS IN EACH PASSAGE THERETHROUGH, THE PASSAGES THROUGH THE GROMMET BEING OF TWO TYPES, THE CONSTRICTIONS IN ONE TYPE OF PASSAGES BEING SUBSTANTIALLY OUT OF TRANSVERSE ALIGNMENT WITH THE CONSTRICTIONS IN THE OTHER TYPE OF PASSAGE, THROUGHOUT A PREDOMINANT PART OF THE GROMMET A PASSAGE OF ONE TYPE BEING LOCATED ADJACENT TO PASSAGES OF THE OTHER TYPE.