Patent Description:
Publication <CIT> discloses a one-piece frame which resiliently supports a plurality of contact fingers. The contact fingers are grouped in two spaced apart generally parallel sets or members which are biased towards one another, with a transverse portion of the frame being disposed therebetween, and opposite ends of each finger extend longitudinally from opposite sides of the transverse portion of the frame.

Publication <CIT> discloses a conductive terminal and an electrical connector including a first terminal and a second terminal stacked on the first terminal. The first terminal has a plurality of first contact portions at an end of the first terminal. A gap is formed between two adjacent first contact portions. The second terminal has a second contact portion at an end of the second terminal. At least a part of the second contact portion extends through the gap of the first terminal.

According to one or more aspects of the present disclosure, an electrical connector configured to interconnect two electrical bus bars includes a first pair of electrical contacts between which the two electrical bus bars are received. Each electrical contact in the pair of electrical contacts having a central base, a first plurality of elongate contact fingers extending longitudinally from the base in a first direction, and a second plurality of elongate contact fingers extending longitudinally from the base in a second direction opposite to the first direction. The electrical connector further includes a second pair of electrical contacts. Each electrical contact in the second pair of electrical contacts has a central base, a first plurality of elongate contact fingers extending longitudinally from the base in the first direction, and a second plurality of elongate contact fingers extending longitudinally from the base in the second direction. The outwardly-oriented surfaces of the second pair of contacts have a different profile than inwardly-oriented surfaces of the first pair of contacts such that the second pair of contacts nest against the first pair of contacts. The outwardly oriented surfaces of the second pair of contacts are in intimate contact with inwardly oriented surfaces of the first pair of contacts. The electrical connector also includes a spring assembly having a retaining band surrounding the bases of the first and second pairs of electrical contacts. The supporting assembly is configured to secure the pair of electrical contacts within the electrical connector. The spring assembly further has a first plurality of elongate spring fingers extending longitudinally from the retaining band in the first direction, and a second plurality of elongate spring fingers extending longitudinally from the retaining band in the second direction, wherein a spring finger of the first or second plurality of spring fingers is in compressive contact with at least one contact finger of the first and second plurality of elongate contact fingers of the second pair of electrical contacts.

In one or more embodiments of the electrical connector according to the previous paragraph, the electrical bus bar assembly, each spring finger of the first and second plurality of spring fingers is in compressive contact with at least one contact finger of the first and second plurality of elongate contact fingers.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, a portion of the at least one contact finger is canted toward a centerline of the electrical connector and a tip of the at least one contact finger is canted away from the centerline of the electrical connector.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, a first material electrically conductive forming the pair of electrical contacts has a higher value of electrical conductivity than a second material electrically conductive forming the spring assembly.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, the first material is a copper-based alloy.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, the second material is a stainless-steel alloy.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, each electrical contact in the first pair of electrical contacts is identical and wherein each electrical contact in the second pair of contact is identical.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, the retaining band defines dovetail features to secure ends of the retaining band to one another.

In one or more embodiments of the electrical connector according to any one of the previous paragraphs, the central bases define tabs extending laterally from the central bases and the retaining band defines apertures in which the tabs are received, thereby securing the first and second pairs of electrical contacts within the electrical connector.

According to one or more aspects of the present disclosure, a method of forming an electrical connector configured to interconnect two electrical bus bars includes the step of forming a first pair of electrical contacts from a sheet of a first electrically conductive material. Each electrical contact in the pair of electrical contacts having a central base, a first plurality of elongate contact fingers extending longitudinally from the base in a first direction, and a second plurality of elongate contact fingers extending longitudinally from the base in a second direction opposite to the first direction. The method additionally includes the step of forming a second pair of electrical contacts from a sheet of the first electrically conductive material so that each electrical contact in the second pair of electrical contacts has a central base, a first plurality of elongate contact fingers extending longitudinally from the base in the first direction, and a second plurality of elongate contact fingers extending longitudinally from the base in the second direction. The method also includes the step of bending a portion of at least one contact finger of the first and second plurality of elongate contact fingers so that it is canted toward a centerline of the electrical connector, wherein outwardly-oriented surfaces of the second pair of contacts have a different profile than inwardly-oriented surfaces of the first pair of contacts. As a further step, the method includes arranging the first and second pairs of electrical contacts such that the second pair of contacts nest against the first pair of contacts and the outwardly-oriented surfaces of the second pair of contacts are in intimate contact with the inwardly-oriented surfaces of the first pair of contacts. As yet another step, the method includes forming a spring assembly from a sheet of a second electrically conductive material. The spring assembly has a retaining band, a first plurality of elongate spring fingers extending longitudinally from the retaining band in the first direction, and a second plurality of elongate spring fingers extending longitudinally from the retaining band in the second direction. The method further includes the step of wrapping the retaining band around the bases of the first and second pairs of electrical contacts, thereby securing the first and second pairs of electrical contacts within the electrical connector and bending a spring finger of the first or second plurality of spring fingers inwardly such that the spring finger is in compressive contact with at least one contact finger of the first and second plurality of elongate contact fingers of the second pair of electrical contacts.

In one or more embodiments of the method according to the previous paragraph, the method further comprises the step of bending each spring finger of the first and second plurality of spring fingers inwardly such that each spring finger is in compressive contact with at least one contact finger of the first and second plurality of elongate contact fingers.

In one or more embodiments of the method according to any one of the previous paragraphs, the first electrically conductive material has a higher value of electrical conductivity than the second electrically conductive material forming the spring assembly.

In one or more embodiments of the method according to any one of the previous paragraphs, the first material is a copper-based alloy.

In one or more embodiments of the method according to any one of the previous paragraphs, the second material is a stainless-steel alloy.

In one or more embodiments of the method according to any one of the previous paragraphs, each electrical contact in the first a pair of electrical contacts is identical and wherein each electrical contact in the second pair of contact is identical.

In one or more embodiments of the method according to any one of the previous paragraphs, the retaining band defines dovetail features to secure ends of the retaining band to one another.

In one or more embodiments of the method according to any one of the previous paragraphs, the central bases define tabs extending laterally from the central bases and the retaining band defines apertures in which the tabs are received, thereby securing the first and second pairs of electrical contacts within the electrical connector.

According to a non-claimed example, the electrical connector also includes a means for applying a compressive force to the pair of electrical contacts. The means is configured to conduct less than <NUM>% of the current flowing through the electrical connector.

<FIG> illustrate examples of an electrical connector <NUM> well suited for high voltage, e.g., over <NUM> volts. The electrical connector <NUM> has a female socket <NUM> at each end that is configured to receive a solid electrical conductor, e.g., a rectangular electrical bus bar (not shown) in each end of the connector. The connector has at least one pair of electrical contacts <NUM> at each end that are configured to receive the bus bars. As best shown in the exploded view of <FIG>, each of the electrical contacts <NUM> has a mesial or central base portion <NUM>. A first plurality of elongate contact fingers 18A extends longitudinally from the base in a first direction and a second plurality of elongate contact fingers 18B extends longitudinally from the base portion <NUM> in a second direction opposite to the first direction. A mesial portion <NUM> of the contact fingers located closest to the base is canted or bent inwardly, i.e., toward a longitudinal central plane <NUM> through the electrical connector <NUM> (see <FIG>) so that the contact fingers <NUM> are in compressive contact with the bus bars when they are inserted within the electrical connector <NUM>. A distal potion or tip <NUM> at the free ends of the contact fingers <NUM> is canted outwardly away from the longitudinal central plane <NUM> to allow the bus bars to more easily be inserted between the contact fingers <NUM>.

The electrical connector also has a spring assembly <NUM> with a retaining band <NUM> that surrounds the bases <NUM> of the electrical contacts <NUM>. The retaining band <NUM> secures the pair of electrical contacts <NUM> within the electrical connector <NUM>. The spring assembly <NUM> further has a first plurality of elongate spring fingers 30A that extend longitudinally from the retaining band <NUM> in the first direction and a second plurality of elongate spring fingers 30B that extend longitudinally from the retaining band <NUM> in the second direction. When the spring assembly <NUM> is assembled to the electrical connector <NUM>, the spring fingers <NUM> are in compressive contact with the contact fingers <NUM> and push the contact fingers inwardly toward the longitudinal central plane <NUM> and the bus bar inserted between the contact fingers <NUM>. The spring fingers <NUM> are configured so that they provide at least <NUM>% of the contact force applied by the electrical connector <NUM> to the bus bars while the contact fingers <NUM> provide <NUM>% or less of the of the contact force applied by the electrical connector <NUM> to the bus bars. The spring fingers <NUM> are bent inwardly at a greater angle than the contact fingers <NUM>, thereby applying a pre-load force to the contact fingers <NUM>.

As shown in <FIG>, there are two pairs of the electrical contacts <NUM>. The inner contacts 14A are not identical to the outer contacts 14B and have a slightly different profile so that the outer contacts 14B will nest against the inner contacts 14A. The inner and outer contacts 14A, 14B on one side of the electrical connector <NUM> are identical to the corresponding inner and outer contacts 14A, 14B on the opposite side. This nesting of the inner and outer contacts 14A, 14B allows an outer side <NUM> of the inner contacts 14A to be in intimate contact with an inner side <NUM> of the outer contacts 14B. This nesting provides an effectively thicker electrical contact within the electrical connector <NUM> that allows a higher value of current to be safely conducted through the electrical connector <NUM>. Further, the nested inner and outer contacts 14A, 14B are also more flexible than contact fingers that have the same effective thickness and that are formed from a single layer of the same material. This flexibility allows the spring assembly <NUM> to apply <NUM>% or more of the contact force which would not be possible with a single layer of the same material. The use of nested inner and outer contacts 14A, 14B also allows the electrical contacts <NUM> to be formed from a thinner material that is less expensive, more readily available, and easier to form than a thicker material. The embodiments of the electrical connector <NUM> shown in <FIG> have two pairs of the electrical contacts while the embodiments of the electrical connector <NUM> shown in <FIG> have three pairs of the electrical contacts. The number of contact fingers <NUM> in the embodiments of the electrical connector <NUM> may also vary as can be seen in <FIG>.

The electrical contacts <NUM> are made of a material that has a higher electrical conductivity value than the material forming the spring assembly <NUM>. For example, the electrical contacts <NUM> may be formed of Cl <NUM> copper alloy which offers high electrical and thermal conductivity. The spring assembly <NUM> may be made of SAE <NUM>½ hard stainless-steel alloy. Due to the higher conductivity of the electrical contacts <NUM>, most of the current passing through the electrical connector <NUM> will pass through the electrical contacts <NUM> rather than the spring assembly <NUM>. Therefore, the properties of the spring assembly <NUM> can be optimized for application of the contact force to the bus bars without consideration of current carrying capabilities. Since the electrical contacts <NUM> provide less than <NUM>% of the spring force, most of the initial spring force will still be provided by the spring fingers <NUM> even if the contact fingers <NUM> relax due to heating because the spring fingers <NUM> are not as susceptible to relaxation due to heating as the copper contact fingers.

In some embodiments, the spring assembly <NUM> is integrally formed from a single piece of sheet metal and in other embodiments, the spring assembly <NUM> is made of two halves that are identical to each other.

The base portions <NUM> of the contacts define tabs <NUM> that extend laterally from the base. The retaining band defines apertures in which these tabs are received within corresponding apertures <NUM> extending through the retaining band <NUM>, thereby securing the electrical contacts within the electrical connector. The retaining band <NUM> may have attachment features <NUM>, such as a dovetail features, which are arranged so that they match up when one end of the retaining band <NUM> is bent to join the other end of the retaining band <NUM>.

A method <NUM> of manufacturing an electrical connector <NUM> is shown in the flow chart of <FIG>. The various steps of the method <NUM> are described below:.

STEP <NUM>, FORM A PAIR OF ELECTRICAL CONTACTS FROM A SHEET OF A FIRST ELECTRICALLY CONDUCTIVE MATERIAL, EACH ELECTRICAL CONTACT IN THE PAIR OF ELECTRICAL CONTACTS HAVING A CENTRAL BASE, A FIRST PLURALITY OF ELONGATE CONTACT FINGERS EXTENDING LONGITUDINALLY FROM THE BASE IN A FIRST DIRECTION, AND A SECOND PLURALITY OF ELONGATE CONTACT FINGERS EXTENDING LONGITUDINALLY FROM THE BASE IN A SECOND DIRECTION OPPOSITE TO THE FIRST DIRECTION, includes forming a pair of electrical contacts <NUM> from a sheet of a first electrically conductive material, each electrical contact 14A, 14B in the pair of electrical contacts <NUM> having a central base portion <NUM>, a first plurality of elongate contact fingers 18A extending longitudinally from the base portion <NUM> in a first direction, and a second plurality of elongate contact fingers 18B extending longitudinally from the base portion <NUM> in a second direction opposite to the first direction;.

STEP <NUM>, BEND A PORTION OF AT LEAST ONE CONTACT FINGER OF THE FIRST AND SECOND PLURALITY OF ELONGATE CONTACT FINGERS SO THAT IT IS CANTED TOWARD A CENTERLINE OF THE ELECTRICAL CONNECTOR AND BENDING A TIP OF THE AT LEAST ONE CONTACT FINGER SO THAT IT IS CANTED AWAY FROM THE CENTERLINE OF THE ELECTRICAL CONNECTOR, includes bending a portion of at least one contact finger <NUM> of the first and second plurality of elongate contact fingers 18A, 18B so that it is canted toward a centerline or the longitudinal central plane <NUM> of the electrical connector <NUM> and bending a tip <NUM> of the at least one contact finger <NUM> so that it is canted away from the centerline or the longitudinal central plane <NUM> of the electrical connector <NUM>;.

STEP <NUM>, FORM A SPRING ASSEMBLY FROM A SHEET OF A SECOND ELECTRICALLY CONDUCTIVE MATERIAL, THE SPRING ASSEMBLY HAVING A RETAINING BAND, A FIRST PLURALITY OF ELONGATE SPRING FINGERS EXTENDING LONGITUDINALLY FROM THE RETAINING BAND IN THE FIRST DIRECTION, AND A SECOND PLURALITY OF ELONGATE SPRING FINGERS EXTENDING LONGITUDINALLY FROM THE RETAINING BAND IN THE SECOND DIRECTION, includes forming a spring assembly <NUM> from a sheet of a second electrically conductive material, the spring assembly <NUM> having a retaining band <NUM>, a first plurality of spring fingers 30A, extending longitudinally from the retaining band <NUM> in the first direction, and a second plurality of spring fingers 30B extending longitudinally from the retaining band <NUM> in the second direction;.

STEP <NUM>, WRAP THE RETAINING BAND AROUND THE BASES OF THE PAIR OF ELECTRICAL CONTACTS, THEREBY SECURING THE PAIR OF ELECTRICAL CONTACTS WITHIN THE ELECTRICAL CONNECTOR, includes wrapping the retaining band <NUM> around the bases <NUM> of the pair of electrical contacts <NUM>, thereby securing the pair of electrical contacts <NUM> within the electrical connector <NUM>;.

STEP <NUM>, BEND A SPRING FINGER OF THE FIRST OR SECOND PLURALITY OF SPRING FINGERS INWARDLY SUCH THAT THE SPRING FINGER IS IN COMPRESSIVE CONTACT WITH AT LEAST ONE CONTACT FINGER OF THE FIRST AND SECOND PLURALITY OF ELONGATE CONTACT FINGERS, includes bending a spring finger <NUM> of the first or second plurality of spring fingers 30A, 30B inwardly such that the spring finger <NUM> is in compressive contact with at least one contact finger <NUM> of the first and second plurality of elongate contact fingers 18A, 18B;.

STEP <NUM>, BEND EACH SPRING FINGER OF THE FIRST AND SECOND PLURALITY OF SPRING FINGERS INWARDLY SUCH THAT EACH SPRING FINGER IS IN COMPRESSIVE CONTACT WITH AT LEAST ONE CONTACT FINGER OF THE FIRST AND SECOND PLURALITY OF ELONGATE CONTACT FINGERS, is an optional step that includes bending each spring finger <NUM> of the first and second plurality of spring fingers 30A, 30B inwardly such that each spring finger <NUM> is in compressive contact with at least one contact finger <NUM> of the first and second plurality of elongate contact fingers 18A, 18B;.

STEP <NUM>, FORM A SECOND PAIR OF ELECTRICAL CONTACTS FROM A SHEET OF THE FIRST ELECTRICALLY CONDUCTIVE MATERIAL, WHEREIN EACH ELECTRICAL CONTACT IN THE SECOND PAIR OF ELECTRICAL CONTACTS HAVING A CENTRAL BASE, A FIRST PLURALITY OF ELONGATE CONTACT FINGERS EXTENDING LONGITUDINALLY FROM THE BASE IN THE FIRST DIRECTION, AND A SECOND PLURALITY OF ELONGATE CONTACT FINGERS EXTENDING LONGITUDINALLY FROM THE BASE IN THE SECOND DIRECTION, is an optional step that includes forming a second pair of electrical contacts 14B from a sheet of the first electrically conductive material, wherein each electrical contact <NUM> in the second pair of electrical contacts 14B having a central base portion <NUM>, a first plurality of elongate contact fingers 18A extending longitudinally from the base portion <NUM> in the first direction, and a second plurality of elongate contact fingers 18B extending longitudinally from the base portion <NUM> in the second direction; and.

STEP <NUM>, BEND THE FIRST AND SECOND PAIRS OF ELECTRICAL CONTACTS SUCH THAT OUTWARDLY ORIENTED SURFACES OF THE SECOND PAIR OF CONTACTS ARE IN INTIMATE CONTACT WITH INWARDLY ORIENTED SURFACES OF THE FIRST PAIR OF CONTACTS, is an optional step that includes bending the first and second pairs of electrical contacts 14A, 14B such that outwardly oriented surfaces or outer sides <NUM> of the first pair of contacts 14A are in intimate contact with inwardly oriented surfaces or inner sides <NUM> of the second pair of contacts 14B.

Accordingly, an electrical connector <NUM> suited for high voltage/current applications and a method <NUM> for manufacturing such an electrical connector is provided. The electrical connector <NUM> and the method <NUM> provide the benefit of an electrical connector that provides a consistent contact force in elevated temperature conditions and over the operating life of the electrical connector. As can be seen in <FIG>, the electrical connector <NUM> is smaller than prior art connector used in similar bus bar connecting applications when shown in the same scale, thereby providing the benefit of requiring less packaging space for the electrical connector <NUM>.

Claim 1:
An electrical connector (<NUM>) configured to interconnect two electrical bus bars, comprising:
a first pair of electrical contacts (14A) configured to receive the two electrical bus bars, each electrical contact (<NUM>) in the pair of electrical contacts (14A) having a central base (<NUM>), a first plurality of elongate contact fingers (18A) extending longitudinally from the base (<NUM>) in a first direction, and a second plurality of elongate contact fingers (18B) extending longitudinally from the base (<NUM>) in a second direction opposite to the first direction;
a second pair of electrical contacts (14B), wherein each electrical contact in the second pair of electrical contacts (14B) has a central base (<NUM>), a first plurality of elongate contact fingers (18A) extending longitudinally from the base in the first direction, and a second plurality of elongate contact fingers (18B) extending longitudinally from the base (<NUM>) in the second direction, wherein outwardly-oriented surfaces of the second pair of contacts (14B) have a different profile than inwardly-oriented surfaces of the first pair of contacts (14A) such that the second pair of contacts (14B) nest against the first pair of contacts (14A), and wherein the outwardly-oriented surfaces of the second pair of contacts (14B) are in intimate contact with the inwardly-oriented surfaces of the first pair of contacts (14A); and
a spring assembly (<NUM>) having a retaining band (<NUM>) surrounding the bases (<NUM>) of the first and second pairs of electrical contacts (14A, 14B) and configured to secure the first and second pairs of electrical contacts (14A, 14B) within the electrical connector (<NUM>), the spring assembly (<NUM>) further having a first plurality of elongate spring fingers (30A) extending longitudinally from the retaining band (<NUM>) in the first direction, and a second plurality of elongate spring fingers (30B) extending longitudinally from the retaining band (<NUM>) in the second direction, wherein a spring finger (<NUM>) of the first or second plurality of spring fingers (30A, 30B) is in compressive contact with at least one contact finger of the first and second plurality of elongate contact fingers (18A, 18B) of the second pair of electrical contacts (14B).