Liquid-tight strain relief
A liquid-tight strain relief includes a tubular-shaped bushing and a dome-shaped gland. The bushing includes a flange with arcuate slots, a centrally-located aperture, a plurality of resilient outer fingers, and a shoe slideably received within a lateral groove of the bushing. The gland includes a head having a centrally-located membrane. The head is co-molded with and encapsulates the flange, resulting in a strain relief having a unitary construction. The strain relief is adapted to be inserted within an orifice of a work piece, and the outer fingers frictionally engage the work piece. A cable is inserted within the strain relief by puncturing the membrane, which then stretches and provides a seal against the cable. The cable is gripped to the strain relief when the shoe is pressed against the cable. The shoe is held against the cable by teeth on the shoe, which engage opposing locking ribs on the bushing.
1. A liquid-tight strain relief, comprising a bushing including a first end, a second end opposite said first end, an outer wall, an aperture extending from said first end to said second end and defining an inner wall, an annular flange extending radially outwardly from said first end, said at least one cutout extending from said outer wall to said inner wall, said at least one cutout defining at least one outer finger, said at least one outer finger adapted to frictionally engage an orifice of a work piece, a cable-gripping shoe slideably received within a lateral recess of the bushing; and a gland including a head having an outer surface, an inner surface, an annular interior portion located within said inner surface and encapsulating said annular flange of the bushing wherein the cable is clamped between the shoe and an arcuate portion of the bushing inner wall opposite the shoe and wherein said gland includes a depression of reduced thickness formed within said outer surface thereof and coaxial with said aperture of said bushing, said depression including a frangible membrane that is adapted to be punctured by an external object inserted into the bushing.
2. The liquid-tight strain relief of claim 1 , wherein said at least one cutout includes a plurality of cutouts.
3. The liquid-tight strain relief of claim 2 , wherein said plurality of cutouts includes two cutouts that are diametrically opposed to one another, and wherein said at least one outer finger includes two diametrically opposed outer fingers each of which is defined by a corresponding one of said two diametrically opposed cutouts.
4. The liquid-tight strain relief of claim 1 , wherein said shoe is affixed to the bushing by the engagement of teeth on the outside of the shoe with at least one inward facing locking rib on the inner wall of the bushing.
5. The liquid-tight strain relief of claim 4 , wherein said shoe is adapted to grip a cable received by the bushing by the application of manual force.
6. The liquid-tight strain relief of claim 1 , wherein said bushing is made from a first material and said gland is made from a second material, said second material having a greater elasticity than said first material.
7. The liquid-tight strain relief of claim 6 , wherein said first material is a thermoplastic material.
8. The liquid-tight strain relief of claim 7 , wherein said second material is a thermoplastic elastomer.
9. The liquid-tight strain relief of claim 1 , wherein said frictionally engaging means of said at least one cutout includes a plurality of outwardly facing ribs.
10. The liquid-tight strain relief of claim 9 , wherein said plurality of cutout ribs is compressible so that the liquid-tight strain relief is adapted to be positioned within the orifice of the work piece.
11. A liquid-tight strain relief, comprising a bushing including a first end, a second end opposite said first end, an outer wall, an aperture extending from said first end to said second end and defining an inner wall, an annular flange extending radially outwardly from said first end, said at least one cutout extending from said outer wall to said inner wall, said at least one cutout defining at least one outer finger, said at least one outer finger adapted to frictionally engage an orifice of a work piece, a cable-gripping shoe slideably received within a lateral recess of the bushing; and a gland including a head having an outer surface, an inner surface, an annular interior portion located within said inner surface and encapsulating said annular flange of the bushing wherein said gland includes a depression of reduced thickness formed within said outer surface thereof and coaxial with said aperture of said bushing, said depression including a frangible membrane that is adapted to be punctured by an external object inserted into the bushing.
12. The liquid-tight strain relief of claim 11 , wherein the external object includes one of a cable, a wire, a tube, and a rod.
13. The liquid-tight strain relief of claim 12 , wherein said membrane is adapted to form a liquid-tight seal around the external object after said membrane is punctured by the external object.
14. A liquid-tight strain relief, comprising a bushing including a first end, a second end opposite said first end, an outer wall, an aperture extending from said first end to said second end and defining an inner wall, an annular flange extending radially outwardly from said first end, said at least one cutout extending from said outer wall to said inner wall, said at least one cutout defining at least one outer finger, said at least one outer finger adapted to frictionally engage an orifice of a work piece, a cable-gripping shoe slideably received within a lateral recess of the bushing; and a gland including a head having an outer surface, an inner surface, an annular interior portion located within said inner surface and encapsulating said annular flange of the bushing wherein the flange has a plurality of arcuate slots extending through the flange from a top side to a bottom side thereof.
15. The liquid-tight strain relief of claim 1 , 11 or 14 wherein the inner wall of the bushing has two diametrically opposed locking ribs that project from its inner wall which engage teeth on the exterior side surfaces of the shoe.
16. The liquid-tight strain relief of claim 1 , 11 or 14 wherein said bushing and said gland are co-molded with one another.
17. The liquid-tight strain relief of claim 1 , 11 or 14 wherein said at least one cutout of said bushing includes a pair of parallel, longitudinal slots, each of which includes a first end located proximate to said first end of said bushing and a second end located proximate to said second end of said bushing, and a transverse slot extending from said first end of one of said longitudinal slots to said first end of the other of said longitudinal slots.
18. The liquid-tight strain relief of claim 14 wherein portions of the gland extend through the slots to the bottom side of the flange thus encapsulating the flange in the area of the slots.