Modular electrical connector assembly providing electrostatic discharge upon insertion of a mating connector

This application claims benefit to Provisional Application No. 60/131,766 filed Apr. 30, 1999.

The present invention relates generally to a modular electrical connector assembly, such as a modular jack, and more specifically to a modular jack which provides electrostatic discharge upon insertion of a mating plug so that problems arising from electrostatic discharge from the plug through the jack to the substrate on which the jack is mounted are avoided.

Data transmission cables which are plugged into units such as hubs, routers and switches, have a tendency to build up static electric charge depending on the environment. When the electrically charged cords are plugged into a data transmission device with a mating connector assembly, such as a computer, this charge can be immediately transferred from the cord through the connector assembly and to the printed circuit board on which the connector assembly is mounted. Depending on the voltages of the electric charge involved, this charge can damage expensive circuitry on the printed circuit board.

It is an object of the present invention to provide new and improved modular connector assemblies wherein electrostatic charge on a data transmission cable being coupled to the connector is discharged and eliminated before the charge is conveyed to a substrate on which the connector assembly is mounted and thereby prevent damage to the circuitry on the substrate.

Accordingly, in order to achieve this object and others, an electrical connector assembly in accordance with the invention includes a jack defining a plug-receiving receptacle, at least one contact having a contact portion situated in the receptacle, the contact portion being electrically couplable to the substrate, and static charge discharge means arranged in electrical connection with the contact(s) for discharging static charge from a plug upon insertion into the receptacle and engagement with the contact(s). The static charge discharge means preferably include a shield surrounding at least a portion of the jack and establish a path to ground from the contact(s) to the ground region of the substrate through the shield. Thus, the plug engages the contact(s) and static charge is eliminated by the connection of the contact(s) to the ground region of the substrate.

The jack may comprise a housing including an outer housing part and an inner housing part situated at least partially in the outer housing part. The outer housing part includes a comb portion defining a plurality of slots, each slot receiving an end portion of a respective contact. The outer housing part includes a channel in communication with all of the slots and possibly extending in a direction perpendicular to a longitudinal direction of the jack. In a preferred embodiment, the static charge discharge means comprises a shorting bar arranged in the channel in engagement with the end portions of the contacts received in the slots. The shorting bar is electrically connected to the shield, e.g., directly or, in the alternative, indirectly through a connecting pin.

The contacts may be unitary contacts, each having, in addition to the contact portion, a terminal portion adapted to be connected to the substrate.

A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily understood by reference to the following detailed description when considered in connection with the accompanying drawings in which:

FIG. 1 is a side view of a modular electrical connector assembly in accordance with the invention; and

FIG. 2 is a partially broken-away view of a modular electrical connector assembly in accordance with the invention.

FIG. 3 is an exploded view of a modular electrical connector assembly in accordance with the invention.

FIG. 4 is a broken-away view of a modular electrical connector assembly in accordance with the invention.

FIG. 5 is a broken-away view of a modular electrical connector assembly in accordance with the invention being used in conjunction with a modular plug.

FIG. 6 is a broken-away view of a modular electrical connector assembly in accordance with the invention being used in conjunction with a modular plug.

Referring now to the drawings wherein like reference characters designate identical or corresponding parts throughout the several views, FIG. 1 shows a side view of a modular electrical connector assembly designated 10 designed for mounting on a substrate such as a printed circuit board. The connector assembly 10 includes a jack 12 and a shield 14 surrounding at least a portion of the jack 12 . Shield 14 is formed from a metallic material and includes projections 14 a adapted to be connected to ground regions of a substrate, such as a printed circuit board, on which the connector assembly 10 is mounted. Jack 12 includes an outer housing part 16 and an inner housing part 18 situated in engagement with and at least partially within the outer housing part 16 to define a plug-receiving receptacle 20 (FIG. 2 ).

The outer and inner housing parts 16 , 18 may have the same general form as existing single-port modular jacks, such as those disclosed in U.S. Pat. No. 4,703,991 (assigned to the current assignee incorporated by reference herein in its entirety). However, differing from the jacks disclosed in the '991 patent, an elongate, substantially cylindrical channel 22 is formed in the comb portion 24 of the outer housing part 16 and at least one side walls of the outer housing part 16 is formed with aperture in alignment with the channel 22 . The comb portion 24 also defines a plurality of substantially parallel slots 26 , each slot 26 being receivable of an end portion 28 a of the contact 28 situated in connection with at least the inner housing part 18 . Channel 22 is open over at least a radial portion thereof to communicate with all of the slots 26 .

The connector assembly 10 also includes a shorting bar 30 arranged in the channel 22 . As shown in FIG. 2, the end portion 28 a of the contacts 28 engages the shorting bar 30 in view of the construction of the contacts 28 to be biased against the lower surface of the slots 26 . The comb portion 24 and channel 22 could be designed such that the end portions 28 a of the contacts 28 contact both the shorting bar 30 and the lower surface of the slots 26 .

The shorting bar 30 is constructed to extend through a side wall of the jack 12 to be connected to the shield 14 and thereby establish an electrical connection between the shorting bar 30 and the shield 14 . Instead of the shorting bar 30 extending through a side wall of jack 12 , the channel 22 and thus the shorting bar 30 could be designed to extend over only the slots 26 and a separate connector pin or any other electrically transmitting member provided to electrically connect the shorting bar 30 to the shield 14 . As known in the art, shield 14 is electrically connected to ground on the printed circuit board on which the connector assembly 10 is mounted. Thus, the shorting bar 30 is connected to ground through the shield 14 of the connector assembly 10 .

The jack 12 also includes terminal portions 32 adapted for connection to the substrate on which the connector assembly 10 is mounted and which may be part of contacts 28 or separate.

In use, prior to insertion of a mating plug into the receptacle 20 , the end portions 28 a of the contacts 28 engage the shorting bar 30 (as shown in FIG. 2 ). As the plug is inserted into the receptacle 20 , any static charge built up on the cable to which the plug is connected is carried away as such charge is transmitted through contacts 28 to the shorting bar 30 and from the shorting bar 30 to the shield 14 and from the shield 14 to the ground on the printed circuit board on which the connector assembly 10 is mounted. This is because the contacts 28 are all in contact with shorting bar 30 when the connector assembly 10 is in an unmated state. After complete insertion of the plug into the receptacle 20 (mating), the end portions 28 a of contacts 28 are urged out of contact with the shorting bar 30 and the shorting bar 30 does not affect data transmission between the plug and connector assembly 10 . Accordingly, using the connector assembly 10 in accordance with the invention, the static charge on the cable to which the plug is attached is discharged and eliminated and is therefore not transmitted to the circuitry on the printed circuit board on which the connector assembly is mounted.

In an alternate embodiment, FIG. 3 shows an exploded view of an electrical connector assembly 10 including jack 12 and shield 14 surrounding at least a portion of jack 12 . Shield 14 is formed from a metallic material and includes projections 14 a adapted to be connected to ground regions of a substrate, such as a printed circuit board, on which the connector assembly 10 is mounted. Jack 12 includes an outer housing part 16 , an inner housing part 18 situated in engagement with and at least partially within the outer housing part 16 , to define a plug-receiving receptacle 20 . It also includes a shorting bar 50 situated within plug-receiving receptacle 20 , between inner housing part 18 and outer housing part 16 . Shorting bar 50 includes grounding projection 52 and spring-like fingers 54 . Grounding projection 52 is adapted to be connected to ground regions of a substrate, such as a printed circuit board, on which the connector assembly 10 is mounted. Alternately, grounding projection 52 can be configured to electrically engage shield 14 and ground through projections 14 a which are adapted to be connected to ground regions of a substrate.

The outer and inner housing parts 16 , 18 may have the same general form as existing single-port modular jacks, such as those disclosed in U.S. Pat. No. 4,703,991 (assigned to the current assignee incorporated by reference herein in its entirety). However, differing from the jacks disclosed in the '991 patent, is the inclusion of the shorting bar 50 in between inner housing part 18 and outer housing part 16 . The comb portion 24 also defines a plurality of substantially parallel slots 26 , each slot 26 being receivable of a finger 54 of the shorting bar 50 . As shown in FIG. 4, the end portions 28 a of the contacts 28 engage the fingers 54 in view of the construction of the contacts 28 to be biased towards the lower surface of the slots 26 .

The jack 12 also includes terminal portions 32 adapted for connection to the substrate on which the connector assembly 10 is mounted and which may be part of contacts 28 or separate.

In use, prior to the insertion of a mating plug into receptacle 20 , the end portions 28 a of the contacts 28 engage the fingers 54 of shorting bar 50 (as shown in FIG. 4 ). As shown in FIG. 5, plug 60 is inserted into the receptacle 20 , plug terminals 62 electrically engage the contacts 28 . During this period of the insertion, end portions 28 a of the contacts 28 remain electrically engaged with fingers 54 of shorting bar 50 . Any static charge built up in the cable to which the plug is connected is carried away as such charge is transmitted from terminals 62 through the contacts 28 to the shorting bar 50 , via fingers 54 , and from shorting bar 50 to the ground, via grounding projection 52 , on the printed circuit board on which the connector assembly 10 is mounted. After complete insertion of plug 60 into receptacle 20 (mating) (FIG. 6 ), the end portions 28 a of contacts 28 are urged out of contact with fingers 54 and the shorting bar 50 does not affect data transmission between plug 60 and connector assembly 10 . Between the period of insertion where plug terminals 62 first engage contacts 28 and complete insertion, fingers 54 , being of a spring-like configuration, follow and remain in electrical contact with the end portions 28 a of contacts 28 for a period of time until they are ultimately urged out of contact with contacts 28 . This extended period of contact allows a more thorough dissipation of static charges to ground than might otherwise be available. Accordingly, using the connector assembly 10 in accordance with the invention, the static charge on the cable to which the plug is attached is discharged and eliminated and is therefore not transmitted to the circuitry on the printed circuit board on which the connector assembly is mounted.

Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. Accordingly, it is understood that other embodiments of the invention are possible in the light of the above teachings. For example, although the outer housing part 16 is provided with a cylindrical channel to accommodate a cylindrical shorting bar, other shapes and forms of a channel and a shorting bar positionable therein are contemplated to be within the scope of the invention. Also, the shorting bar may take the form of one or more electrically connected elements and other means for establishing a path from the contact(s) or shorting bar to ground can be provided which do not require electrical conveyance through a shield.

Further, the shorting bar in accordance with the invention can be used in numerous different types of jacks and connector assemblies and is not limited to the particular construction of the jack, i.e., including an inner housing part and an outer housing part, shown in FIGS. 1 and 2. Rather, connector assemblies in accordance with the invention may include, in addition to a shorting bar engaging with the end portions of the contacts, either a plurality of contact/terminal wires (each having a contact portion situated in the plug-receiving receptacle and a terminal portion adapted for attached to the substrate on which the connector assembly is mounted) or for example, a first set of contacts including the contact portion and being attached to an internal printed circuit board and a second set of contacts including the terminal portion and also being attached to the internal printed circuit board. In this regard, reference is made to U.S. Pat. No. 5,736,910 (assigned to the current assignee and incorporated by reference herein in its entirety). The first and second set of contacts and internal printed circuit board would thus constitute transmission means for transmitting data from the plug to the substrate. Furthermore, the shorting bar in accordance with the invention can be incorporated into multi-port and multi-level modular connectors.