Seals for an electrical connector

Abstract: An electrical connector (10) comprising a housing (14,22) having at least one rib (52) provided thereon, a seal member (30) positioned in the housing (14,22), the seal member (30) having at least one groove (50) which extends from a first surface (34) of the seal member (30) toward a second surface (32), the rib (52) is dimensioned to be wider than the groove (50) such that the rib (52) will cause the seal member to be compressed between the rib (52) and the housing (14,22).

Description: The present invention relates to seals for electrical connectors such as are used in automobiles, trucks and tractors. In particular, this invention relates to an electrical connector according to the pre-characterizing portion of claim 1. Seals for electrical connectors are well known in the art; e.g., from documents US-A-4,973,268 and US-A-4,998,896. From document EP-A2-0,335,721 a waterproof electrical connector has come to be known. This prior art uses a rubber gasket to be sandwiched between a cap and a housing. The rubber gasket has an outer limit at least on one of its opposite surfaces to permit the complemental outer limit of the inner surface of the cap or the rear end of the housing to fit in. The rubber gasket has at least one groove formed on a surface thereon. The housing is provided with a rib being wider than the groove. It is now proposed to provide a seal for the receptacle half having an orientation feature and a seal for the header half having a combined peripheral and compression sealing. The present invention is given by an electrical connector exhibiting the features of claim 1. Dependent claims 2 and 3 exhibit further improvements of the subject-matter of claim 1. According to the present invention, seals for an electrical connector are provided wherein one seal includes grooves in a body portion which cooperates with ribs on an end cap to ensure proper assembly in addition to the sealing function. A second seal includes a rim portion having an outwardly facing mating surface for compression sealing and an inwardly facing surface for compression sealing and an inwardly facing surface for peripheral sealing. The invention will now be described by way of example with reference to the accompanying drawings in which: Fig. 1 is an exploded view of a receptacle of an electrical connector using a seal of the present invention; Fig. 2 is a view of the seal of the receptacle; Fig. 3 is a view of a seal for pin header; Fig. 4 is a sectioned view of the seal; Fig. 5 shows the receptacle and sectioned header prior to being joined; and Fig. 6 shows the joined receptacle and sectioned header. With reference to Fig. 1 , receptacle 10 includes terminal position assurance member 12, housing 14, socket terminals 18, rear seal 20 and rear face cap 22. With reference to Figures 1 and 2, rear seal 20 includes a body portion 30 with front and rear surfaces 32,34 respectively and edge surface 36 therebetween. Passages 40, on the same pattern as cavities in housing 14, extend through body portion 30 as does a centrally located large opening 42. The surfaces defining passages 40 and opening 42 are provided with inwardly projecting annular sealing ridges 44. Outwardly projecting sealing ridges 46 are provided on edge surface 36. As shown in Figure 2, a set of four, longitudinally extending grooves 50 are provided in rear surface 34 of body portion 30. Grooves 50 are located between rows of passages 40 and on each side of opening 42. Returning to Figure 1, ribs 52 are provided on the inside surface 54 of rear face cap 22. These ribs 52 are on the same spacing as are grooves 50 on surface 34 of seal 20. Grooves 50 and ribs 52 provide an orientation feature which prevents rear seal 20 from being assembled incorrectly. Besides providing a physical indicator, the grooves 50 provide a visual indicator. Further, ribs 52 are slightly wider than grooves 50 so that upon assembly, the seal material of body portion 30 is compressed between the ribs 52 and side walls 56 of cap 22. Because of this compression, the thickness of body portion 30 is substantially less than what would otherwise be required for adequate sealing. With reference to Figures 3 and 4, seal 102 includes body portion 104 and rim portion 106. Passages 108 in body portion provide access for pin terminals 110 (Figure 6) and rectangular hole 112 provides access for a jackscrew 113 (Figure 6). Rim portion 106 includes an outwardly facing mating surface 114, a first inwardly facing surface 116 and a second inwardly facing surface 118. Body portion 104 and rim portion 106 define space 120. Seal 102 is preferably molded with a suitable material such as silicon rubber. The geometry of rim portion 106 provides peripheral and compression sealing in the same space as a compression-only seal would occupy and less space than a traditional peripheral seal. Further, the seal geometry requires less force to compress seal 102. Figures 5 and 6 illustrate the use of seal 102 in pin header 122 for sealing the juncture with receptacle 10. Seal 102 is positioned on the base or floor 124 of cavity 126 of header 122 with terminals 110 extending through passages 108 (Figure 4). As receptacle 10 and header 122 are joined to provide electrical connector 130, edge 14b of housing 14 slides along first inwardly facing surface 116 and edge 14a of housing 14 engages mating surface 114. As receptacle 10 and header 122 are tightened up, the seal material beneath surface 114 is displaced such that the second inwardly facing surface 118 bulges out into space 120 (not shown). Displacing the material requires less force to compress a compression-type seal and solves a problem that was discovered during the testing of connector 30 with a prior art seal, i.e., that in a high temperature environment, the seal material expanded and induced internal stresses in plastic components 10,122 with the result that shrinkage occurred and the components 10,122 drew apart, creating leaks pass the seal. The displacement reduces the compression forces imposed on seal 102 and accordingly less internal stressing is induced into the receptacle 10 and header 122. Peripheral sealing is obtained between side 14b of housing 14 and the first inwardly facing surface 116. As can be discerned from the foregoing description, seals for an electrical connector has been disclosed. One seal includes an orientation feature which, in cooperation with an end cap, prevents incorrect assembly. Another seal provides a combination peripheral and compression sealing which reduces internal stresses which can occur in the plastic components and thereby insures continual sealing during elevated temperature exposures.

Claims: An electrical connector (10) a) comprising a housing (14, 22) having at least one rib (52) provided thereon; b) a seal member (30) positioned in the housing (14, 22), c) the seal member (30) having at least one groove (50) formed in a surface (34) of the sealing member (30), d) the rib (52) is dimensioned to be wider than the groove such that the rib (52) will cause the seal member to be compressed between the rib (52) and the housing (14, 22), characterized in that: e) the at least one groove (50) extends longitudinally between rows of passages (40) formed in the sealing member (30). An electrical connector (10) as recited in claim 1, characterized in that the housing (14, 22) has a cap (22), the at least one rib (52) being positioned on an inside surface (54) of the cap (22). An electrical connector (10) as recited in claims 1 or 2, characterized in that the at least one rib (52) and the at least one groove (50) provide an orientation feature which prevents the seal member (30) from being assembled incorrectly.

Inventors: CRAVENS DAVID MARTIN, DENLINGER KEITH ROBERT, GRYZBOWSKI RICHARD WAYNE, MYER JOHN MARK, CRAVENS, DAVID MARTIN, DENLINGER, KEITH ROBERT, GRYZBOWSKI, RICHARD WAYNE, MYER, JOHN MARK
Applicants: WHITAKER CORP, THE WHITAKER CORPORATION
Application year: 1992
Main classification: H01R13
IPC codes: H01R13