Patent Application
20090186518
1. Field of the Invention
The invention relates to an electrical connector and, more particularly, to an electrical connector with grooves and ridges.
2. Brief Description of Prior Developments
U.S. Pat. No. 2,375,741 discloses a splice electrical connector having a general tube shape with a bore having serrations along its length. U.S. Pat. No. 2,490,809 discloses a coil spring with knurling or milling on its inner and outer sides used in a splice electrical connector.
Prices for raw materials for making electrical connectors continues to be a difficulty in maintaining the cost-effective design of products used in the utility, construction, maintenance, and repair industries. With respect to electrical products fabricated from copper and aluminum, a tremendous surge in cost (per fabricated dollar of raw materials) has resulted in the development of measures to control cost of new designs fabricated from these materials. Also, there has been a wholesale change in using alternate alloys in the design of these products going forward. Further, the increased use of batteries as remote energy providers in many power tools, specifically battery powered crimping tools, has placed tremendous emphasis on the optimization of battery life to increase the functionality for the user.
There is a desire to reduce costs associated with the purchase of raw materials used to manufacture electrical connectors. In addition, there is also a desire to provide electrical connectors which require less energy to crimp with battery powered crimping tools and, therefore, help to prolong battery life of the crimping tool.
In accordance with one aspect of the invention, an electrical connector is provided including a tube having a conductor receiving channel which is substantially closed except at one or more ends of the channel. The tube includes an exterior surface having longitudinal grooves and ridges along a longitudinal length the tube.
In accordance with another aspect of the invention, an electrical connector is provided having a general tube shape with a conductor receiving channel. The channel is substantially closed except at opposite ends of the channel. An interior surface of the connector at the channel comprises longitudinal grooves and ridges along a longitudinal length of the connector. An exterior surface of the connector at the channel comprises longitudinal grooves and ridges along the longitudinal length of the connector.
In accordance with another aspect of the invention, a method of manufacturing an electrical connector comprising extruding a tube of metal having a conductor receiving channel which is closed except at opposite ends of the channel; and forming longitudinal grooves and ridges on an exterior surface of the tube along a longitudinal length of the tube.
The foregoing aspects and other features of the invention are explained in the following description, taken in connection with the accompanying drawings, wherein:
Referring to
The invention is particularly applicable to copper or aluminum tubular compression lugs, splices, and taps. The invention provides a novel approach to the design of these types of electrical connectors which optimizes material content; while at the same time providing for increased surface area in the ‘finished’ connection. This increases the ability of the connector to transfer energy, in the form of heat, to atmosphere more efficiently. This results in a cooler connection that will, therefore, result in an increased life expectancy. Further, this type of design would decrease the amount of time required to complete a crimping operation by a battery operated hydraulic crimping tool, thereby extending battery life of the tool.
In the embodiment shown in
One purpose of the ridges 18 and grooves 20 is to provide a heat transfer surface on the exterior side 16 of the connector for heat transfer to the surrounding environment; such as surround air. Thus, the ridges 18 form heat transfer fins for this purpose. With the embodiment shown, one method of forming the connector 10 is by an extrusion process. During the extrusion process the ridges 18 and grooves 20 can be formed at the same time as the rest of the connector. This provides a very efficient and inexpensive method for forming the connector with an integral exterior side enhanced heat transfer system.
Another purpose of the ridges 18 and grooves 20 is to reduce the amount of material necessary to form the connector 10. More specifically, volumes of material are absent between the adjacent ridges 18 where the grooves 20 are now located. The connector 10 is still able to function as an electrical connector, but with use of less material to form the connector. Use of less material to form the connector 10, versus a similar conventional connector which does not have the grooves 20, allows the connector 10 to be manufactured less expensively than the conventional connector.
Referring also to
As noted above, the connector 10 is generally adapted to be compressed onto electrical conductors (not shown) to mechanically and electrically splice the conductors together. An example of a battery powered hydraulic crimping tool for this purpose is shown in
In a preferred embodiment, the electrical connector has a rifled exterior (ridges and grooves) that would provide an average of about 17 percent additional surface area to the lug before crimping occurs. Of course, after the barrel of the connector is crimped by the tool 28, the rifling at the exterior (and/or interior) would not be that same percentage. However, an increase in surface area is still apparent; especially between crimps in the area of the connector exterior which was not crimped. Further, this design would allow the material to flow to its completely crimped state with less mechanical resistance since there is less overall material to deform; thereby decreasing the overall amount of time required to crimp the connector. For battery operated crimping tools used to crimp this type of connector, the decrease in crimping time would result in an increase in battery life per charge. So, not only does the connector shape optimize the material content and thermal characteristics of the product, but also the amount of time required to complete a crimping operation.
Alternate embodiments can be ascertained, such as rifled interior and exterior surfaces, interior only, and rifled in the form of various shapes and helical variations, and are apparent and included in the scope of this invention. One type of such alternate embodiment is shown in
The primary purpose of the interior rifling (ridges and grooves) is to use less material to form the connector 42; and thus make the connector less expensive to manufacture. However, the interior rifling also allows the reduced amount of material to flow to its completely crimped state with less mechanical resistance (since there is less overall material to deform); thereby decreasing the overall amount of time required to crimp the connector. For battery operated crimping tools used to crimp this type of connector, the decrease in crimping time would result in an increase in battery life per charge. So, not only does the connector shape optimize the material content and thermal characteristics of the product, but also the amount of time required to complete a crimping operation.
These ridges 56 and grooves 58 are provided for the same reasons as the ridges 18 and grooves 20. In particular, the ridges 56 and grooves 58 allow less material to be used in order to form the connector 44; the missing material at the grooves 58 being less. The ridges 56 also form heat transfer fins. Although a portion of the barrel section 46 will be deformed during crimping, some portions of the ridges will still remain after crimping; such as in front of and behind the crimp location. The formation of the barrel section 46 having less material than a conventional lug connector also allows a battery operated crimping tool to crimp the barrel section 46 onto a conductor faster and with less resistance; thereby helping to prolong battery life of the crimping tool before recharging is necessary.
Referring now to
The development of ‘rifled’ (either helically or straight) tubing exteriors (and/or interiors) results in slightly less material by weight per connector, but would be a thermal heat sink and provide ‘fins’ in the form of grooves along the outer diameter of the connector for heat dissipation and material optimization. ‘Rifling’ the interior of the same lug would in fact result in material optimization, and may also allow the conductors inserted into the lug to form more contact spots with the inner diameter of the connector, thereby increasing electrical efficiency in the form of increased contact area.
It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. For example, features recited in the various dependent claims could be combined with each other in any suitable combination(s). Accordingly, the invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.
