Electrical conductor splicing assembly having spring with opposite end portions captured by and interconnecting conductor gripping members

An electrical conductor splicing assembly includes a tubular shell, and a pair of tubular gripping members and a spring disposed within an interior chamber of the shell. The shell and gripping members are electrically conductive. Each gripping member defines a longitudinal passageway and a cavity within an inner portion in communication with the passageway. The shell and gripping members receive an end of an electrical conductor through each opposite end portion of the shell and within each gripping member. The spring is disposed between the gripping members and has a main portion, a pair of opposite end portions and a pair of reduced diameter portions interconnecting the main portion to the opposite end portions. The opposite end portions of the spring are captured within the cavities of the gripping members. The reduced diameter portions of the spring are disposed adjacent to and extend away from the cavities of the gripping members. The main portion of the spring urges the gripping members away from one another outwardly toward the opposite end portions of the shell which have oppositely tapered configurations. The spring causes the gripping members to abut against the opposite end portions of the shell and press radially inwardly toward and grip the conductors inserted through the gripping members and thereby provide a splice-type electrical connection between the conductors via the gripping members and shell. The reduced diameter portions of the spring block the ends of the conductors from passing farther into the shell through the main portion of the spring located between the gripping members.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention generally relates to splicing devices for connecting
 electrical conductors and, more particularly, is concerned with an
 electrical conductor splicing assembly having a spring with opposite end
 portions captured by and interconnecting conductor gripping members.
 2. Description of the Prior Art
 Splicing devices are used to connect electrical conductors to one another.
 A variety of splicing devices are known in the prior art. Such splicing
 devices typically include a tubular shell, a plurality of conductor
 gripping members, one or more springs and one or more conductor stopping
 members. The shell may be one piece and have a pair of tapered opposite
 end portions. The gripping members are generally disposed within the
 shell. The one or more springs are generally interposed between and urge
 the gripping members outwardly toward the tapered opposite end portions of
 the shell causing the gripping members to grip the conductors inserted
 therethrough. The one or more stopping members may be disposed between or
 at opposite ends of the one or more springs to capture or block the ends
 of the conductors.
 Representative examples of prior art splicing devices and the like are
 disclosed in U.S. Pat. No. 1,657,253 to Fortin, U.S. Pat. Nos. 1,854,782
 and 1,854,783 to Cook, U.S. Pat. No. 1,997,649 to Ohlund, U.S. Pat. No.
 2,041,108 to Becker, Sr., et al., U.S. Pat. Nos. 2,063,718 and 2,078,051
 to Berndt, U.S. Pat. No. 2,120,469 to Kyle, U.S. Pat. No. 2,144,050 to
 Fotsch, U.S. Pat. No. 2,166,458 to Berndt et al., U.S. Pat. No. 2,434,358
 to Frank, U.S. Pat. No. 2,521,722 to Hubbell et al., U.S. Pat. No.
 2,572,940 to Lockhart, U.S. Pat. Nos. 2,859,424 and 3,166,373 to Berndt
 and U.S. Pat. No. 4,362,352 to Hawkins et al. While these prior art
 splicing devices may be satisfactory in use under the specific conditions
 for which they were designed, none of them seem to provide a simple and
 comprehensive solution for the splicing of electrical conductors.
 Consequently, a need remains for further innovations which will provide an
 optimum solution for splicing electrical conductors without introducing
 any new problems that will replace those of the prior art.
 SUMMARY OF THE INVENTION
 The present invention provides an electrical conductor splicing assembly
 designed to satisfy the aforementioned need. The electrical conductor
 splicing assembly of the present invention includes a pair of conductor
 gripping members and a single spring disposed within a tubular shell. The
 spring has opposite end portions captured within cavities of the gripping
 members. The spring urges the gripping members away from one another and
 outwardly within tapered opposite end portions of the shell and causes the
 gripping members to grip electrical conductors inserted therethrough. The
 spring also has a pair of reduced diameter portions each disposed adjacent
 to one of the opposite end portions of the spring. The reduced diameter
 portions of the spring block the ends of the conductors from passing
 farther into the shell beyond the gripping members and toward one another.
 The combination of the spring and gripping members allows the shell to
 have a minimum length and the splicing assembly to have a minimum number
 of parts.
 Accordingly, the present invention is directed to an electrical conductor
 splicing assembly which comprises: (a) a tubular shell made of a
 substantially electrically conductive material and having opposite ends, a
 middle portion and opposite end portions extending between the middle
 portion and opposite ends and tapering from the middle portion to the
 opposite ends, the shell defining an interior chamber open at the opposite
 ends of the shell; (b) a pair of tubular conductor gripping members made
 of a substantially electrically conductive material and disposed within
 the interior chamber of the shell, each of the gripping members having
 opposite inner and outer ends and defining a longitudinal passageway open
 at the inner and outer ends, the shell and gripping members being adapted
 for receiving an end portion of an electrical conductor through each of
 the opposite ends and within the interior chamber of the shell and through
 the outer end and within the passageway of each of the gripping members;
 and (c) a spring disposed within the interior chamber of the shell between
 the gripping members and having a main portion, a pair of opposite end
 portions and a pair of intermediate portions each disposed between and
 interconnecting one of the opposite end portions of the spring to the main
 portion thereof, the spring being mounted at the opposite end portions
 thereof to the inner ends of the gripping members and urging the gripping
 members away from one another outwardly toward the opposite ends of the
 shell and causing the gripping members to abut against the opposite end
 portions of the shell and press radially inwardly toward and grip the end
 portions of the electrical conductors received within the passageways and
 thereby provide an electrical connection between the electrical conductors
 via the gripping members and shell. The intermediate portions of the
 spring are disposed adjacent to the inner ends of the gripping members and
 are adapted to block the end portions of the electrical conductors from
 passing farther into the shell through the main portion of the spring
 located between the gripping members.
 More particularly, the intermediate portions of the spring have diameters
 which are reduced in size relative to diameters of the opposite end
 portions of the spring. Further, the diameters of the intermediate
 portions of the spring are reduced in size relative to a diameter of the
 main portion of the spring. Each gripping member has an inner portion and
 an outer portion extending and tapering from the inner portion to the
 outer end of the gripping member. Each gripping member defines a cavity
 within the inner portion thereof in communication with the longitudinal
 passageway. The opposite end portions of the spring are captured within
 the cavities of the gripping members.
 Each gripping member is internally threaded within the longitudinal
 passageway thereof adjacent to and interiorly of the outer end of the
 gripping member for gripping the end portion of the electrical conductor
 inserted into the longitudinal passageway of the gripping member. Each
 gripping member has a plurality of longitudinal slots spaced apart
 circumferentially from one another. Each slot extends interiorly from the
 outer end toward the inner end of the gripping member and is in
 communication with the longitudinal passageway of the gripping member. The
 longitudinal slots divide the gripping member into longitudinal segments
 which may be pressed radially inwardly toward one another for gripping the
 end portion of the electrical conductor inserted therebetween. One of the
 plurality of slots of each gripping member extends from the outer end to
 the inner end of the gripping member such that the gripping member may be
 pulled apart at the one slot for placing one of the opposite end portions
 of the spring within the cavity of the gripping member.
 These and other features and advantages of the present invention will
 become apparent to those skilled in the art upon a reading of the
 following detailed description when taken in conjunction with the drawings
 wherein there is shown and described an illustrative embodiment of the
 invention.

DETAILED DESCRIPTION OF THE INVENTION
 Referring to the drawings and particularly to FIGS. 1 to 3, there is
 illustrated an electrical conductor splicing assembly, generally
 designated 10, of the present invention. The splicing assembly 10 is for
 providing an electrical connection between a pair of electrical conductors
 C. Each electrical conductor C is in the form of a copper wire or any
 other suitable type of conductor. The splicing assembly 10 basically
 includes a tubular shell 12, a pair of tubular conductor gripping members
 14, and a spring 16. The tubular shell 12 and the gripping members 14 are
 made of a substantially electrically conductive material, such as copper
 or any other suitable material.
 Referring now to FIGS. 1 to 5, the tubular shell 12 of the assembly 10 has
 a pair of opposite ends 12A, a middle portion 12B and a pair of opposite
 end portions 12C. The middle portion 12B has a substantially cylindrical
 configuration with a diameter substantially uniform along its length. The
 opposite end portions 12C extend in opposite directions from the middle
 portion 12B to the opposite ends 12A thereof. The opposite end portions
 12C are substantially identical to one another and have a length greater
 than the length of the middle portion 12B. Each opposite end portion 12C
 has a diameter which gradually decreases from the larger diameter of the
 middle portion 12B to the smaller diameter of one of the opposite ends
 12A.
 The tubular shell 12 defines an interior chamber 18 open at the opposite
 ends 12A of the shell 12. The interior chamber 18 has a configuration
 defined by and thus substantially the same as the configurations of the
 middle portion 12B and the opposite end portions 12C of the shell 12. The
 interior chamber 18 has a length which is slightly less than the combined
 lengths of the middle portion 12B and the opposite end portions 12C. The
 shell 12 also defines a pair of end passages 20 each disposed at and
 extending interiorly through one of the opposite ends 12A of the shell 12
 and in communication with the interior chamber 18. The end passages 20
 have substantially circular configurations in transverse cross-section
 with the same diameter substantially uniform along their lengths. Each
 electrical conductor C has a diameter which is less than the diameter of
 the end passages 20 such that the electrical conductor C may be inserted
 therethrough.
 Referring now to FIGS. 2 to 5, the tubular gripping members 14 of the
 assembly 10 are disposed within the interior chamber 18 of the shell 12.
 The gripping members 14 have substantially identical conical
 configurations which substantially conform to the tapered configurations
 of the opposite end portions 12C of the shell 12. Each gripping member 14
 is disposed within one of the opposite end portions 12C of the shell 12
 and has an axial length which is less than the length of one of the
 opposite end portions 12C of the shell 12. More particularly, each
 gripping member 14 has opposite inner and outer ends 14A, 14B, an inner
 portion 14C and an outer portion 14D. The inner portion 14C has a
 substantially cylindrical configuration and a diameter which is
 substantially uniform along its length and less than the diameter of one
 of the opposite end portions 12C of the shell 12 adjacent to the middle
 portion 12B of the shell 12. The outer portion 14D extends and tapers from
 the inner portion 14C to the outer end 14B. The outer portion 14D has an
 axial length which is greater than the axial length of the inner portion
 14C. The outer portion 14D has a diameter which gradually decreases from
 the inner portion 14C to the outer end 14B. The gradually decreasing
 diameter of the outer portion 14D is less than that of one of the opposite
 end portions 12C of the shell 12 for most of the length of the one
 opposite end portion 12C. The diameter of the inner portion 14C, however,
 is greater than the gradually decreasing diameter of the one opposite end
 portion 12C of the shell 12 for most of the length of the one opposite end
 portion 12C such that the size of the inner portion 14C restricts movement
 of the gripping member 14 toward and at a point where the outer end 14B of
 the gripping member 14 is spaced from an adjacent opposite end 12A of the
 shell 12.
 Each gripping member 14 defines a longitudinal passageway 22 open at the
 inner and outer ends 14A, 14B of the gripping member 14. More
 particularly, the longitudinal passageway 22 is defined within the outer
 portion 14D of the gripping member 14 and has a substantially circular
 configuration in transverse cross-section. The longitudinal passageway 22
 is substantially aligned with the end passage 20 at the adjacent opposite
 end 12A of the shell 12. The axial length of the longitudinal passageway
 22 is substantially the same as the length of the outer portion 14D. The
 diameter of the longitudinal passageway 22 is substantially uniform along
 its length and is less than the diameter of one of the end passages 20 of
 the shell 12. Each gripping member 14 defines a cavity 24 within the inner
 portion 14C in communication with the longitudinal passageway 22. The
 cavity 24 is open at the inner end 14A and to the longitudinal passageway
 22. The cavity 24 has a substantially circular configuration in transverse
 cross-section. The length of the cavity 24 is slightly less than the
 length of the inner portion 14C. The diameter of the cavity 24 is
 substantially uniform along its length and is slightly less than the
 diameter of the inner portion 14C and is substantially greater than the
 diameter of the longitudinal passageway 22. Each gripping member 14
 defines an inner end opening 26 disposed at the inner end 14A. The inner
 end opening 26 is formed by a circumferential lip 14E being beveled
 interiorly toward a central longitudinal axis A of the gripping member 14
 and being open at and about the central longitudinal axis. The inner end
 opening 26 and lip 14E both have a substantially circular configuration.
 The inner end opening 26 has a diameter which is greater than the diameter
 of the longitudinal passageway 22 and the diameter of one of the end
 passages 20 of the shell 12.
 The end portion P of the electrical conductor C may be inserted through one
 of the end passages 20 and into the adjacent portion of the interior
 chamber 18 of the shell 12 and into the longitudinal passageway 22 and
 through the cavity 24 to the inner end 14A and into the inner end opening
 26 of a gripping member 14. Each gripping member 14 can be internally
 threaded at 28 within the longitudinal passageway 22 adjacent to and
 interiorly of the outer end 14B of the gripping member 14 for gripping the
 end portion P of the electrical conductor C inserted into the longitudinal
 passageway 22 of the gripping member 14, as shown in FIG. 2. The internal
 threads 28 may extend any suitable distance into the longitudinal
 passageway 22. When the end portion P of the electrical conductor C is
 inserted into and through the passageway 22 of the gripping member 14, the
 outer portion 14D of the gripping member 14 may need to be somewhat
 expanded circumferentially as the diameter of the electrical conductor C
 may be somewhat greater than the diameter of the longitudinal passageway
 22, as shown in FIG. 5. For permitting such expansion, each gripping
 member 14 has a plurality of longitudinal slots 30 spaced apart
 circumferentially from one another and each extending interiorly from the
 outer end 14B toward the inner end 14A and defined in communication with
 the longitudinal passageway 22 of the gripping member 14. Each gripping
 member 14, preferably, defines four longitudinal slots 30 which are spaced
 an equal distance apart from one another. Each of three of the slots 30 is
 defined completely through the outer portion 14D and partially through the
 inner portion 14C of the gripping member 14. One of the slots 30 extends
 from the outer end 14B to the inner end 14A and is defined completely
 through each of the outer portion 14D and the inner portion 14C of the
 gripping member 14. The slots 30 divide the gripping member 14 into
 longitudinal segments 32. Each segment 32 has a volume which is
 substantially the same as the volume of each of the other segments 32. The
 segments 32 may be pressed radially inwardly toward one another and toward
 the longitudinal passageway 22 of the gripping member 14 for gripping the
 electrical conductor C inserted therethrough. This segmentation of each
 gripping member 14 allows the outer portion 14D of the gripping member 14
 to be deformed outwardly away from the central longitudinal axis A of the
 gripping member 14 when the end portion P of the electrical conductor C is
 inserted within the longitudinal passageway 22 and to be deformed inwardly
 toward the central longitudinal axis A when gripping the end portion P of
 the electrical conductor C. Since each of the segments 32 are
 substantially the same size, the force of the outer portion 14D of the
 gripping member 14 against the end portion P of the electrical conductor C
 is distributed evenly around a circumference thereof.
 Referring now to FIGS. 2 to 7, the spring 16 of the assembly 10 is disposed
 within the interior chamber 18 of the shell 12 between the gripping
 members 14. The spring 16 is disposed mostly within the middle portion 12B
 and only partially within each of the opposite end portions 12C of the
 shell 12. The spring 16 is preferably a coil type. The spring 16 has a
 main portion 34, a pair of opposite end portions 36 and a pair of
 intermediate portions 38 each disposed between and interconnecting one of
 the opposite end portions 36 to the main portion 34. The intermediate
 portions 38, particularly, have reduced diameters, that is, their coils
 have diameters which are reduced in size relative to the diameters of the
 coils of the main portion 34 and of the opposite end portions 36. The
 spring 16 has a length greater than the length of the middle portion 12B
 of the shell 12 but less than the combined lengths of the middle portion
 12B and the opposite end portions 12C of the shell 12. The coils of the
 opposite end portions 36 have diameters which are substantially the same
 as the diameters of the cavities 24 of the inner portions 14C of the
 gripping members 14.
 The spring 16 is mounted at its opposite end portions 36 to the gripping
 members 14 adjacent to the inner ends 14A of the gripping members 14 with
 the opposite end portions 36 of the spring 16 being disposed and captured
 within the cavities 24 of the gripping members 14 defined by the inner
 portions 14C thereof. The opposite end portions 36 of the spring 16 are
 placed into the cavities 24 by pulling the gripping member 14 apart along
 the one longitudinal slot 30 which extends all the way through each of the
 outer and inner portions 14D, 14C of the gripping member 14. The spring 16
 urges the gripping members 14 away from one another outwardly toward the
 opposite ends 12A of the shell 12 and causes the gripping members 14 to
 abut against the opposite end portions 12C of the shell 12 and press
 radially inwardly toward the central longitudinal axis A of the gripping
 members 14 and grip the end portions P of the electrical conductors C
 inserted therethrough and thereby provide an electrical connection between
 the electrical conductors C via the electrically conductive gripping
 members 14 and shell 12.
 The intermediate, or reduced diameter, portions 38 of the spring 16 are
 disposed adjacent to and, particularly, are aligned with the inner ends
 14A and are exteriorly of the inner end openings 26 of the gripping
 members 14. Each reduced diameter portion 38 has a middle coil 38A and a
 pair of opposite end coils 38B. The diameter of the middle coil 38A is
 less than the diameters of the opposite end coils 38B and less than the
 diameter of the end portion P of the electrical conductor C. The diameter
 of each of the opposite end coils 38B is greater than the diameter of the
 end portion P of the electrical conductor C and less than the diameter of
 the coils of the main portion 34 and opposite end portions 36 of the
 spring 16. The diameter of the coils of the opposite end portions 36 is
 greater than the diameter of the inner end opening 26 defined by the
 circumferential rim 14E of each of the gripping members 14 such that each
 of the opposite end portions 36 of the spring 16 are captured and retained
 within the cavities 24 of the gripping members 14. One of the opposite end
 coils 38B of each of the intermediate or reduced diameter portions 38 of
 the spring 16 is disposed just exteriorly of the inner end opening 26 and
 within the beveled portion of the inner end 14A of each of the gripping
 members 14. The middle coil 38A of each of the reduced diameter portions
 38 of the spring 16 is disposed partially within the beveled portion and
 just exteriorly of the inner end 14A of each of the gripping members 14.
 Each reduced diameter portion 38 of the spring 16 blocks the end portion P
 of the given electrical conductor C and prevents its from passing farther
 into the shell 12 through the main portion 34 of the spring 16 located
 between the gripping members 14. The blocking of the end portions P of the
 electrical conductors C, particularly, occurs at the middle coil 38A of
 each reduced diameter portion 38 of the spring 16.
 It is thought that the present invention and its advantages will be
 understood from the foregoing description and it will be apparent that
 various changes may be made thereto without departing from the spirit and
 scope of the invention or sacrificing all of its material advantages, the
 form hereinbefore described being merely preferred or exemplary embodiment
 thereof.