Not applicable.
This invention relates to wire connectors. In particular, this invention relates to a wire connector in which blades pierce the insulation of wires to establish an electrical connection.
Typically, wires have a metallic core surrounded by an insulating coating. When a current is run through the metallic core of the wire, the insulating coating assures that the current is contained within the insulation and does not deviate outside of the wire due to a short. When performing electrical work, it may be necessary to join wires at a connection such that a current may safely travel from one wire to another. Forming a connection between wires may be done in a number of ways.
One method of connecting wires is to have a conductive blade or blades clamp down on the wire to pierce the insulating coating surrounding the wire. If the blade pierces the insulating coating such that the conductive blade contacts the metallic core, then an electrical connection may be formed between the conductive blade and the metallic core that the blade contacts. Such connections are common in attaching plugs to data cables or audio-video cables.
However, forming such connections commonly require that a crimping tool be used to force the blade into the wire insulation. Furthermore, the connectors and tools are typically adapted for forming a specific connection (i.e., inserting wires of a certain gage into a specific type of connector for a particular application).
Hence, there is a need for an improved means for connection of wires given the varied nature of electrical work and the wires to be connected.
The present invention provides an insulation displacement connector for the easy connection of a set of wires, including wires of different gages.
According to one form of the invention, an insulation displacement connector includes a housing, a metal insert, and a handle. The housing defines at least one channel for receiving at least one wire from at least one point of wire insertion. The housing further defines a track that intersects at least one channel. The metal insert has a body portion with at least one blade extending therefrom. The metal insert is located in and slideably moveable within the track such that a portion of the at least one blade can move into and out of at least one channel of the housing. The handle has a cam portion and is rotatable relative to the housing about an axis that runs through the cam portion of the handle. The cam portion selectively contacts the body portion of the metal insert as the handle is rotated about the axis. The insulation displacement connector has an open position in which at least one wire can be received by at least one channel and a closed position in which the cam portion of the handle forces at least one blade of the metal insert into at least one channel to pierce the insulation of any wire contained therein.
According to another form of the invention, the insulation displacement connector includes a plurality of channels and a metal insert slideably moveable in a track. The plurality of channels are for receiving a plurality of wires along a direction of wire insertion. Accordingly, each of the channels extend from a corresponding opening for insertion of one of the wires. The metal insert is slideably moveable in a track and has a first row of blades and second row of blades that selectively intersect the channels. The first row and the second row of blades each have a plurality of pairs of blades. There is a gap between the blades of each pair. The gap between the blades of each pair of blades in the first row is greater than the gap between the blades of each pair of blades in the second row. The pairs of blades of the first row of blades can intersect the corresponding channels at an intersection proximal the corresponding opening of each of the channels, while the pairs of blades of the second row of blades intersect corresponding channels at an intersection distal the corresponding opening of each of the channels. In both the first and second row of blades, the gap between the pairs of blades extends laterally across the corresponding channel relative to the direction of wire insertion. Further, each of the channels reduce in effective diameter between the first row of blades and the second row of blades. Thus, if a relatively larger diameter wire is inserted into the channels, then the channels restrict the insertion depth of the relatively larger diameter wire so that it does not reach the second row of blades. However, the channels permit a relatively smaller diameter wire to be inserted such that it can reach the second row of blades. When the metal insert is forced into the channels, so as to pierce an insulation covering of each of the wires, electrical contact is made between the first row of blades and the relatively larger diameter wires and electrical contact is made between the second row of blades and the relatively smaller diameter wires.
These and still other advantages of the invention will be apparent from the detailed description and drawings. What follows is merely a description of a preferred embodiment of the present invention. To assess the full scope of the invention the claims should be looked to as the preferred embodiment is not intended to be the only embodiment within the scope of the claims.
Referring first to
The plurality of openings 14 extend into the housing 12 as a plurality of channels 16, which taper inward as they extend away from the plurality of openings 14. Although the inward taper may be gradual over the distance of each of the plurality of channels 16, the plurality of channels 16 may include a step 18 on a portion of the taper. The step 18 provides a portion of the channel having a steeper rate of taper towards the axis of the channel than the rate of taper for the rest of the channel.
It should appreciated that although the plurality of channels 16 have been described as tapered, that the plurality of channels 16 do not need to be round in cross section or tapered. Rather, the plurality of channels 16 have an effective diameter that reduces as the plurality of channels 16 extend away from the plurality of openings 14 along a direction of wire insertion between the first row of blades 36 and the second row of blades 38, as will be described below. The effective diameter, as used herein, is used to describe the largest diameter circle that could be circumscribed in a cross section of the channel perpendicular to the direction of wire insertion at each of the various points along the channel. Thus, the plurality of channels 16 can have “effective diameters” even while taking on a cross sectional shape resembling a square, triangular, rectangle, oval, and the like. Moreover, rather than tapering, the plurality of channels 16 may incorporate stepped segments or the like.
A handle 20 with a cam portion 22 is rotatably attached to the housing 12. As shown, a shaft 24 extends through the cam portion 22 of the handle 20 and into apertures 26 in the housing 12, such that the handle 20 pivots about an axis of rotation A-A that runs through the cam portion 22. The shaft 24 could be integrally formed as a part of the handle 20 or formed separately from the handle 20.
The handle 20 may also include a groove 28. The groove 28 may be shaped for matching engagement with a finger or thumb when the handle 20 is being depressed.
As can be seen most clearly in
Referring now to
In one form, the gap 42 between each of the plurality of pairs of blades 40 in the first row of blades 36 is approximately 0.055 inches while the gap 46 between each of the plurality of pairs of blades 44 in the second row of blades 38 is approximately 0.03 inches. These values correspond to appropriate gaps for straddling and contacting the metallic core of particular gages of wire as will be described in more detail below. However, the particular values of the gaps may be changed to accommodate different gage wires.
Further, and referring to
Referring back to
As shown in
It should be noted that the metal insert 30 can be retained in the up position with the channels clear by frictional force between the track 32 and the metal insert 30. However, other biasing mechanisms such as, for example, a spring, magnets, or the like may be used to maintain the up position of the metal insert 30 in the open position. Additionally, the metal insert 30 and track 32 may be formed such that they loosely fit together with an interference fit.
Referring now to
Although the open position is shown as the position in which the handle 20 is up and the closed position is shown as the position in which the handle 20 is down, it should be appreciated that the open and closed positions are in fact determined by the orientation of the cam portion 22 and the position of the metal insert 30. When the cam portion 22 of the handle 20 contacts the surface of the body 34 of the metal insert 30 such that the cam portion 22 forces the blades of the metal insert 30 into the plurality of channels 16, then the handle 20 can be said to be in a closed position. However, when the metal insert 30 is able to move into and out of the plurality of channels 16 because the cam portion 22 does not restrict the body 34 of the metal insert 30, then the insulation displacement connector 10 is in the open position. However, the geometry of the handle 20 (i.e., the orientation of the cam portion 22 of the handle 20 relative to the lever portion of handle 20) may be such that it is differently located from the housing 12 in the open and closed positions.
Further, the handle 20 may have a locking portion 48 and the housing 12 may have a locking portion 50, such that when the handle 20 is moved to a closed position that is proximate the housing 12, then the locking portion 48 of the handle 20 interlocks with the locking portion 50 of the housing 12. In this way, the handle 20 may be locked such that the cam portion 22 will not freely rotate and allow the blades to disengage from the wires, thus breaking the electrical connection.
It should be appreciated that an upward force on the locking portion 48 of the handle 20 can cause the locking portions 48 and 50 of the handle 20 and the housing 12 to disengage from one another such that the handle 20 might be lifted back up.
Referring now to
When the blades of the metal insert 30 enter the plurality of channels 16, then the blades may pierce the insulation coating any wires contained in the plurality of channels 16 to contact the metallic core of the wires. In particular, when the blades of the metal insert 30 enter the plurality of channels 16, the blades descend on opposite sides of the channel, such that the gap between the blades extends along a plane perpendicular to a direction of wire insertion and the gaps between each of the pairs of blades extends across the channel in a direction perpendicular to the direction of wire insertion.
Referring now to
As shown in
As can be seen in
The plurality of channels 16 reduce in effective diameter between the first row of blades 36 and the second row of blades 38 to determine the insertion depth of different diameter wires. If a plurality of wires 52 including relatively larger diameter wires and relatively smaller diameter wires is inserted into the plurality of channels 16, then reduction in effective diameter of the plurality of channels 16 restricts the insertion depth of each of the plurality of wires 52 having a relatively larger diameter so that they do not extend to the second row of blades 38. Likewise, the plurality of channels 16 permit each of the plurality of wires 52 having a relatively smaller diameter to reach the second row of blades 38. When the metal insert 30 is forced into the plurality of channels 16 to pierce an insulation covering of each of the plurality of wires 52, electrical contact is made between the first row of blades 36 and the relatively larger diameter wires and electrical contact is made between the second row of blades 38 and the relatively smaller diameter wires.
It is contemplated that the portion of the channels proximate the openings may be designed to receive 12-14 AWG wire and that the portion of the channels further from the openings (i.e., deeper in the channel) may be designed to receive 16-18 AWG wire. However, the channels may be designed to accommodate wires of other gages.
Once the plurality of wires 52 are received in the plurality of openings 14, the handle 20 may be moved from the open position (as shown in
Because the metal insert 30 is substantially surrounded by the housing 12 and the handle 20 in the closed position which can both be made on a non-conductive material, the metal insert 30 can conduct a current between the plurality of wires 52 while being electrically isolated from its surroundings.
As can be seen in
When the restrictive insertion is coupled with the fact that the rows of blades of the metal insert 30 have various size gaps therebetween, it is possible to ensure that each of the plurality of wires 52 have their insulation pierced and the metallic core contacted by a set of blades with an appropriately-sized gap therebetween as seen in
If only one set of blades were present, then the insulation displacement connector 10 would not be well-suited to connect wires of substantially different diameters. If only one set of blades were available, then the blades would need to have a gap therebetween that was sufficiently small to ensure contact with the metallic core of the smallest wire upon piercing of the insulation. However, having a small gap between the blades to accommodate for small diameter wires creates force insertion problems when contacting wires having a large diameter metallic core. In order to force a set of blades with a small gap into or around the metallic wire core with a large diameter, at least one of the blades and wire must be deformed. Inducing this deformation requires that a great amount of force be applied to the blade. This makes it difficult to finger operate the connector or necessitates the use of a tool to apply a sufficient insertion force. Having two sets of blades, arranged in the manner described above, means that blades with a gap similar to the diameter of the metallic core can pierce the wire, thus reducing the force required to bite down on the wires to form the connection.
However, merely having two sets of blades with various-sized gaps between the blades will not ensure that the set of blades with the appropriate gap therebetween will pierce the blades. For example, if not for the reduction in effective diameter of the channels, then a large diameter wire could be deeply inserted into the channel to the back row of blades with the smaller blade gap. If this were to happen, then a large insertion force would be required to have the rear set of blades clamp down on the wire. The reduction in effective diameter of the channel restricts the insertion depth of the larger diameter wires to ensure that only a set of blades having an appropriate gap clamp down on the wire in the channel.
Further, the placement of the step 18 between the points of intersection between the track 32 and the plurality of channels 16 will further selectively restrict the insertion depth of the wires in the plurality of channels 16. As the thickness of the insulation surrounding the metallic core of a wire may vary among different types of wires, the diameter of the wire is not always a sufficient predictor of the metallic core contained therein. However, it is fairly reasonable to expect that within a certain range of diameters for the insulation that a corresponding range of diameters for the metallic core is likely. Thus, the step 18 can be used to ensure that a wire with a relatively thin layer of insulation, but with a large diameter metallic core does not get deeply inserted into the smaller diameter portions of the plurality of channels 16.
As can be seen best in
Thus, the present invention provides an insulation displacement connector that is suitable for the tool-less connection of wires of various gages. The combination of channels having a reduction in effective diameter and blades having various gaps restricts the insertion of the wires such that an appropriately-sized pair of blades can pierce the insulation to contact the metallic core of each wire. Because of this configuration, the wire connector does not require excessive force to bite down on the wires. Because a large force is not required, the insulation displacement connector can be finger operated and no separate tool is necessary.
Preferred embodiments of the invention have been described in considerable detail. Many modifications and variations to the preferred embodiments described will be apparent to a person of ordinary skill in the art. Therefore, the invention should not be limited to the embodiments described.
This application claims the benefit of U.S. provisional patent application 60/933,643 filed on Jun. 7, 2007 and U.S. provisional patent application 61/128,742 filed on May 23, 2008. The contents of these patent applications are hereby incorporated by reference in their entirety.
Number | Name | Date | Kind |
---|---|---|---|
2609415 | Benander et al. | Sep 1952 | A |
2627537 | Weisberg | Feb 1953 | A |
3388370 | Elm | Jun 1968 | A |
3793611 | Johansson et al. | Feb 1974 | A |
3793612 | Driscoll | Feb 1974 | A |
3858157 | Bazille, Jr. | Dec 1974 | A |
3877774 | Dorrell | Apr 1975 | A |
4037905 | Lucas | Jul 1977 | A |
4793823 | Cozzens et al. | Dec 1988 | A |
4995829 | Geib et al. | Feb 1991 | A |
5080606 | Burkard | Jan 1992 | A |
5961341 | Knowles et al. | Oct 1999 | A |
6468103 | Brower | Oct 2002 | B1 |
6500020 | Vo et al. | Dec 2002 | B2 |
Number | Date | Country | |
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20080305675 A1 | Dec 2008 | US |
Number | Date | Country | |
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60933643 | Jun 2007 | US | |
61128742 | May 2008 | US |