IL48078A

IL48078A - Moisture sealing grommet for an electrical connector

Info

Publication number: IL48078A
Application number: IL48078A
Authority: IL
Inventors: G Swanson
Original assignee: Bendix Corp
Priority date: 1974-10-02
Filing date: 1975-09-11
Publication date: 1977-07-31
Also published as: CA1052881A; FR2287096B1; FR2287096A1; DE2542627C2; DE2542627A1; GB1458959A; JPS5917487B2; IL48078A0; IT1043023B; JPS5162394A

Description

sealing connecto 45775 Moisture Sealing Grommet and Electrical Connector Incorporating A The invention relates to a moisture sealing grommet and to a connector of the type incorporating such a The invention is more particularly related to the grornmet in the rear of the electrical connector that prevents moisture from entering the Electrical connectors generally include a cylindrical a dielectric insert mounted in the a plurality of electrical contacts arranged in spaced relationship in the dielectric and a for receiving wires that are attached to respective electrical contacts and to provide a seal at the rear of the connector prevent moisture from entering into the connector and adversely affecting the The the moisture seal between the grommet and the incoming the longer the life and stable operation of the electrical Because of the density of the contacts in a present day electrical certain problems have with respect to maximizing the sealing effectiveness of the For the more pressure exerted against the incoming wires by the the better the sealing increasing the sealing pressure on the grommet generally resulted in distortion of the grommet which then results in contact between the grommet and the incoming Another problem associated with sealing out moisture between the grommet and the incoming wires was that the configuration of the incoming wire receiving passages was such that stresses were set up within the grommet so that when wires were pulled through the the grommet tore between adjacent thereby reducing the effectiveness or eliminating the seal between adjacent passages and One attempt to minimize the problems is to provide a grommet which includes at least two constrictio To minimize the constrictions this type of grommet arranged so that they are substantially out of transverse alignment with the constriction of an adjacent A not so obvious defect in this type of grommet is the fact that the grommet is generally molded from rubber and therefore this type of configuration does not permit the use of core pins that are less than A core pin creates a constriction in the passage that exerts pressure against a wire in the thereby providing a pressure tight moisture if a core pin of inches the constrictions in the passages would be smaller and more pressure would be applied against the aforesaid thereby improving the sealing teristics with respect to small diameter wires having a diameter just slightly greater than the diameter of the constriction in the passageway of the In order to avoid these the present invention proposes a moisture sealing grommet adapted for sealing a plurality of wires passing therethrough said grommet comprising a body having a front a rear face and a plurality of parallel wire receiving passages extending through said body from the front face to the rear said grommet being characterized in that each of said passages includes a cylindrical portion and a curvilinear portion that diverges outwardly in the direction of said rear face and extends to said rear said curvilinear portion having a minimum diameter which is less than the diameter of the cylindrical and a maximum diameter at said rear face which is greater than the diameter of the cylindrical According to a particular embodiment of the the ratio of the distance from the cylindrical portion to the minimum diameter of the curvilinear portion with respect to the distance from the cylindrical portion to the maximum diameter of the curvilinear portio is greater than r n sa ous a p ura y of wire receiving electrical contacts mounted in said and a grommet for sealing a plurality of wires connected to respective contacts characterized in that said grommet is of the above defined The invention will now be by way of an with reference to the accompanying drawings in FIGURE 1 is an end elevation of the grommet utilized in conjunction with an insert of a connector FIGURE 2 is a diagrammatic view of the grommet shown in FIGURE 1 and which incorporates the principles and objects of this FIGURE is an enlarged view of one of the passages through the grommet that emphasizes the pertinent characteristics of the passage extending through the FIGURE is a partial diagram of a grommet that illustrates a wire passing through a passageway in the Referring now to the FIGURE 1 illustrates a grommet 10 that is utilized in an electrical connector assembly to provide a seal between the wires passing therethrough into a connector housing The grommet 10 includes a plurality of closely spaced passages each of which are adapted to receive a wire that passes into the connector assembly and is attached to an electrical The grommet 10 is generally shaped and comprised of electrically insulating rubber or material of intermediate The grommet 10 located at one end of a assembly is in tight contact with the housing of the electrical connector to prevent moisture from entering into the connector and generally has one face FIGURE to a dielectric insert that holds the electrical a rear face and a plurality of axially aligned passages in saced relationship that extend through the grommet 10 from the front face 11 to the rear face Each of the passages includes a cylindrically shaped portion 20 and a curvilinear portion 30 that diverges outwardly to the rear face 12 from a constricted portion contiguous with the cylindrical portion of the The curvilinear portion 30 of the passageways as one may be called a Vest or FIGURE 3 is an enlarged partial diagrammatic view of one of the passageways through the grommet 10 which emphasizes the important aspects and features of the As can be seen from FIGURE the cylindrical portion 20 of the passageway includes a wall 21 and the curvilinear portion of the passageway includes a wall of The curvilinear portion 30 of the passageway preferably has a fixed radius of curvature R and diverges outwardly to an opening D3 in the rear face 12 of the grommet The point of origin of the radius R is preferably along line which is a distance Yl from the junction between the curvilinear portion and the cylindrical portion 20 of the The curvilinear design of the passageway tributes to reducing in or eliminating stresses when the grommet 10 is subjected to pressure by an incoming The best location for the narrowest constriction D2 within the curvilinear passageway is a distance Yl from the cylindrical portion which is less than the distance which is the axial length of the curvilinear portion of the A preferred of the distance Y2 to Yl is one wherein Y2 is greater than Yl FIGURE 4 illustrates a grommet which has a wire 40 which passe through the passage in the grommet FIGURE 4 illustrates how the walls of the curvilinear portion of the passageway are in contact with the wire 40 to prevent moisture from D2 in the curvilinear portion of the passageway so that when wire is drawn through the the walls 31 of the curvilinear which are resiliently come into contact with the wire to form a An advantage of this grommet over prior art grommets is that the special contour of the passages 30 provides support for a wire while maintaining a seal between the wire and grommet even when the wire is pulled to one side or around the opening in a The curvilinear passage 30 also guides and contac insertion and removal tools A removal especiall used with a small diameter has tendency to cut into the walls of a grommet having only a cylindrical The curvilinear shape of the passage aids in aligning a contact removal tool so that it does not cut into the 31 of the passage While a preferred embodiment of the invention has been disclosed it will be apparent to those skilled in art that changes may be made to the invention as set forth in the appended claims is some certain features of the invention may used to advantage without corresponding use of it is intended that the illustrative and descriptive materials herein be used to illustrate the principles of the invention and not to limit the scope insufficientOCRQuality

Claims

WHAT IS CLAIMED IS: .

1. A moisture sealing grom et adapted for sealing a plurality of wires passing therethrough, said grommet comprising a body having a front face, a rear face and a plurality of parallel wire receiving passages extending through said body from the front face to the rear face, wherein each of said passages includes a cylindrical portion and a curvilinear portion that diverges outwardly in the direction of said rear face and extends to said rear face, said curvilinear portion having a minimum diameter which is less than the diameter of the cylindrical portion, and a maximum diameter at said sear face which is greater than the diameter of the cylindrical portion.

2. A grommet as claimed in Claim 1, wherein the ratio of the distance from the cylindrical portion to the minimum diameter of the curvilinear portion with respect to the distance from the cylindrical portion to the maximum diameter of the curvilinear portion is greater than 1.5·

3. A grommet as claimed in either Claim 1 or 2, wherein each of said passages is adapted to receive a wire, the diameter of which wire being greater than the minimum diameter of the curvilinear portion and smaller than the maximum diameter of the curvilinear portion.

4. A grommet as claimed in any one of the preceding claims wherein said grommet is comprised of a single unitary piece made of soft elastomeric material.

5. An electrical connector of the type having a housing, an insert in said housing, a plurality of wire receiving electrical contacts mounted in said insert, and a grommet for sealing a plurality of wires connected to respective contacts, wherein said grommet is of the type claimed in any one of the preceding claims.

6. A grommet substantially as illustrated and as described with reference to the accompanying drawings.