Armored flexible electrical conduit with fittings

Abstract

An angularly adjustable angularly adjustable electrical conduit fitting includes an articulate metal conduit bendable at least 90 degrees about an arc having an inside radius of curvature not exceeding 12 inches, the conduit in its preferred from being between 193/4 and 203/4 inches long in a contracted state and being extendable by between 21% and 23% of its contracted length and having at one end a conduit coupling and at its opposite end a conduit or wall opening connector.

Description

This application is a reissue of Ser. No. 07/893,794 filed Jun. 4, 1992 now U.S. Pat. No. 5,283,393.16 which includes an upper cylindrical wall or section 17 and a lower coaxial cylindrical wall or section 18 of greater diameter than that of upper section 17 and joined thereto by an upwardly inwardly inclined annular flange 19. An upwardly arcuate peripheral flange 20 projects outwardly from the upper edge of upper section 17 and terminates in a depending coaxial cylindrical wall 21 which defines a hook vertical free leg. A downwardly convex arcuate peripheral flange 22 projects inwardly from the lower edge of lower cylindrical section 18 and terminates in an upwardly directed coaxial cylindrical wall 23 which defines a hook vertical free leg. The radial outer face of each cylindrical wall 21 overlies and slidably engages and is shorter than the inside face of the lower section 18 of the next successive upper segment 14 and the radial inner face of each cylindrical wall 23 overlies, and is shorter than and slidably engages the radial outer face upper section 17 of the next successive segment 14. The conduit 11 may be longitudinally extended and contracted while being hermetically closed by the close sliding engagement between cylindrical walls 17 and 23 and cylindrical walls 21 and 18 and may be bent in any desired direction while being in a hermetically closed condition with different amounts of relative movement between walls 17 and 23 and walls 21 and 18 at opposite sides of the conduit 11.

One end of conduit flexible 11 is affixed to a female compression fitting 12 of known construction, the fitting 12 having a short tubular projection telescoping the end of conduit 11 which is tightly clamped thereto by a peripheral strap 26 tightly encircling and radially compressing the outer end border of conduit 11 to the telescoping tubular projection strap 26 abutting a peripheral head formed on fitting 12. Alternatively, compression fitting 12 ma may be fastened to conduit 11 in various manners, such as welding or the like. Fitting 12 is provided with a gland nut 27 which when tightened compresses a gland or gasket encircling a conduit inserted into fitting 12 to clamp the conduit and effect a hermetically tight coupling in the known member. The male fitting 13 is affixed to the opposite end of flexible conduit 11 in the manner described above in connection with fitting 12, the fitting 13 including a tubular stub portion 28 of the diameter of the standard electrical conduit having the standard EMT diameter and mates the standard conduit (EMT) coupling or connector.

In coupling a pair of conduits or a conduit with a conduit fitting with the electrical fitting device 10, an end of the conduit is telescoped into a respective fittings 12 and clamped fitting 13 is inserted into another female conduit fitting engaging the end of another conduit or other device, the length and flexibility of conduit 11 permitting the adjustment of device 10 to compensate for the spacing and angular deviations of the conduits or related fittings. The fitting 12 is tightened in the usual manner. If one end of a conduit is to be connected to the aperture wall of a circuit breaker or junction box, the fitting 13 is substituted by a conduit engagable fitting having a threaded tubular shank with a peripheral shoulder at its base and insertable through the wall aperture and secured to its border by a matching nut in the known manner. As in conventional fittings, a cable, for example, an insulation covered multiple conductor cable 29 of lesser thickness than flexible conduit 11 and its end fittings 12 and 13 and the connecting conduits traverse the lengths of the conduits and fittings.

As an example of the improved device 10, conduit 11 is 31/32 inches in outside diameter, 201/4 inches long in its contracted condition, extendable by 22% of its contracted length, bendable about a 12 inch radius of curvature for 90 degrees. It should be understood that the above dimensions and parameters may be modified, for example, as earlier explained.

As shown in FIG. 4 of the drawings 9 which FIG. 4 illustrates another embodiment of the present invention which differs from that first described in the construction of the flexible conduit 33 which may be substituted for the conduit 11. The conduit 33 differs from conduit 11 in that a peripheral groove 34 is formed in each cylindrical wall 36 which defines a hook vertical free leg which slidably engages the confronting face of the conduit inside wall 37. Nesting in and filling each groove 34 and tightly slidably engaging wall 37 is an annular packing 39 formed of cotton or other suitable packing material to assure a rain tight and concrete tight relationship between successive conduit segments. In all other respects, the device last described is similar in structure, configuration and application to that first described.

While there has been described and illustrated preferred embodiments of the present invention, it is apparent that numerous alternations, omissions and additions may be made without departing from the spirit thereof.

Claims

1. An angularly adjustable electrical conduit fitting device comprising an extendible and contractible flexible conduit bendable at least to 90 degrees about a curve having an inside radius not exceeding 12 inches and an electrical fitting secured to and communicating with each end of said conduit, at least one of said fittings being an electrical conduit connector, said conduit being articulate and including a plurality of successive relatively longitudinally slidable segments interlocked against longitudinal separation, each of said segments including a cylindrical body portion having an upper section terminating at its top in an inwardly directed peripheral flange joined to a depending cylindrical upper hook free leg and a lower section coaxial with and of lesser diameter than said upper section and terminating at its bottom in an outwardly directed peripheral flange joined to an upwardly projecting cylindrical lower hook free leg, said depending upper hook free leg having an inner face slidable engaging the outside face of the lower section of the next successive upper segment and said upwardly projecting lower hook free leg having an outside face slidably engaging the inside face of the upper section of the next successive lower segment, one of said hook legs of each of said segments having formed in the face thereof confronting the opposing face of said cylindrical body a peripheral groove, and further including a packing located in said groove and engaging said opposing face.

2. The device of claim 1 wherein said conduit in its fully contracted state is between 193/4 and 203/4 inches long.

3. The device of claim 3 1 wherein said conduit is extendable from its fully contracted state between 21% and 23%.

4. The device of claim 1 wherein said conduit has an inside diameter between 2.735 and 2.765 inches. 5. The device of claim 1 further comprising a packing located in said groove and engaging said opposing face.6. The device of claim 1 wherein said extendible and contractible flexible conduit is bendable to at least 90 degrees about a curve having an inside radius not exceeding 12 inches.7. An angularly adjustable electrical conduit fitting device comprising:

(a) an extendible and contractible flexible conduit which comprises a helically wound strip which forms a plurality of successive relatively longitudinally slidable segments wherein each said slidable segment is interlocked with adjacent successive slidable segments, each said slidable segment comprises:

(i) an upper section having an upwardly directed interior wall terminating at its top with an outwardly projecting arcuate peripheral flange which terminates with a downwardly directed exterior wall,

(ii) a lower section having a downwardly directed exterior wall terminating at its bottom with an inwardly projecting arcuate peripheral flange which terminates with an upwardly directed interior wall, and

(iii) a means for connecting said upper and lower sections of said slidable segment together,

wherein said slidable segment is connected to the next successive lower slidable segment and to the next successive upper slidable segment such that said lower section of said slidable segment is coaxial with said upper section of said next successive lower slidable segment wherein said downwardly directed exterior wall of said upper section of said next successive lower slidable segment having an outer surface slidably engaging an inner surface of said downwardly directed exterior wall of said lower section of said slidable segment and wherein said lower section of said next successive upper slidable segment is coaxial with said upper section of said slidable segment wherein said downwardly directed exterior wall of said upper section of said slidable segment having an outer surface slidably engaging an inner surface of said downwardly directed exterior wall of said lower section of said next successive upper slidable segment; and

(b) an electrical fitting secured to and communicating with each end of said conduit.8. The device of claim 7 wherein said conduit in its fully contracted state is between 193/4 and 203/4 inches long.9. The device of claim 8 wherein said conduit is extendable from its fully contracted state between 21% and 23%.10. The device of claim 7 wherein said conduit has an inside diameter between 2.735 and 2.765 inches.11. The device of claim 7 further comprising a peripheral groove formed in said upwardly directed interior wall of said lower section of said slidable segments.12. The device of claim 11 further comprising a packing located in said peripheral groove and engaging the respective inner surface of said upwardly directed interior wall of said upper section of said next successive slidable segment.13. The device of claim 7 wherein said extendible and contractible flexible conduit is bendable to at least 90 degrees about a curve having an inside radius not exceeding 12 inches.