Patent Publication Number: US-4582382-A

Title: Electrical connector for oxidized surface

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to electrical connectors. More specifically, the present invention is directed to an electrical connector for an oxidized surface. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an improved electrical connector for an ozidized surface. 
     In accomplishing this and other objects, there has been provided, in accordance with the present invention, an electrical connector having a first group of parallel legs, each having a free standing barb on a free first end thereof, the points of said barbs being arranged in a facing relationship and having a spacing less than the thickness of a plate to be straddled by said legs, a second group of parallel legs, each having a free standing barb on a free first end thereof, said barbs on said second legs being arranged in a facing relationship and having a spacing less than the thickness of a plate to be straddled by said second legs and a longitudinal spine having said first legs attached to a first side of said spine and said second legs attached to a second side of said spine, said spine, said barbs and said first and second legs being made of an electrically conductive material. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A better understanding of the present invention may be had when the following detailed description is read in connection with the accompanying drawings, in which: 
     FIG. 1 is a pictorial illustration of the electrical connector of the present invention used in an electrostatic precipitator; 
     FIG. 2 is a side view of the electrical connector of the present invention used in the environment shown in FIG. 1; 
     FIG. 3 is a bottom view of a second embodiment of the electrical connector of the present invention and 
     FIG. 4 is a side view of the electrical connector shown in FIG. 3. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1 in more detail, there is shown a partial pictorial illustration of an electrostatic precipitator having a plurality of contaminent collector plates 2. Typically, these plates 2 are made of aluminum which is normally covered with an aluminum oxide on its surface. In order to provide an effective electrical connection to the collector plates 2, an electrical connector 4 has to penetrate the aluminum oxide surface coating while presenting a low resistance surface to a spring-loaded wiping arm 6 which, in turn, is connected to a terminal board 8 for supplying a high voltage to the collector plates 2 by a power supply (not shown). 
     In FIG. 2, there is shown a side view of the electrostatic precipitator environment shown in FIG. 1 having a plurality of collector plates 2. An embodiment of the electrical connector 4 of the present invention is arranged to bridge a pair of the collector plates 2 by utilizing a center spine section 10 having a pair of integrally formed parallel legs 12, 14 extending perpendicular to the bridge section and a similar pair of perpendicular legs 16, 18 arranged along the other side of the bridge section 10. Each of the legs 12, 14, 16 and 18 is provided with a integrally formed free-standing barb, e.g., barbs 12a, 14a, 16a and 18a. 
     The barbs for each pair of legs, e.g., barbs 12a, 14a for legs 12, 14, is arranged with the points of the barbs in a facing relationship and spaced apart by a distance less than the thickness of the plates 2. The barbs 12a, 14a, 16a and 18a may each be formed in the legs 12, 14, 16 and 18 by selectively shearing the metal from the respective legs. The legs and the barbs provide a means for penetrating the surface oxide coating on the aluminum plates 2 by a scraping action of the barbs as the connector 4 of the present invention is pushed onto to the collector plates 2. The connector 4 is preferably made of an electrically conductive material having a low resistance non-oxidizing surface such as phospor bronze to provide a means for effecting a low resistance electrical connection to the spring 6. 
     As shown in FIG. 3, a second embodiment of the connector 4 includes additional parallel legs 20, 22 along the spine 10 having respective barbs 20a and 22a. From this figure, it may be seen that legs 12 and 18 are formed at one end of the spine 10 while the legs 14 and 16 are offset from the legs 12 along the spine 10 to enable the connector legs to be integrally formed from a single piece of metal forming the connector 4. The additional legs 20,22 are parallel to the aforesaid legs 12, 14, 16 and 18 and are substantially a duplicate of the legs 12 and 18 although located at the other end of the spine 10 from the legs 12 and 18. Accordingly, each group of legs, e.g., legs 12, 14 and 20 is arranged to straddle one of the plates 2 while the corresponding barbs 12a, 14a and 20a are arranged to penetrate the plate&#39;s surface oxide. Similarly, the other group of legs 16, 18 and 22 provide a similar function with respect to an adjacent one of the plates 2. The additional barbs 20a and 22a on the additional legs 20 and 22 provide an additional oxide penetrating surface and also balance the offset relationship of the legs 12, 14, 16 and 18 along the spine 10 to facilitate the mounting of the connector 4 on the plates 2 by assisting the locating of plates 2 between the legs during the mounting of the connector 4 on the plates 2. In FIG. 4, there is shown a side view of the connector shown in FIG. 3. In summary, the attachment of the connector 4 to the collector plates 2 provides a high unit force contact to penetrate the aluminum oxide by a scraping action which further assures a continued good electrical connection by preventing an oxide build-up between the connector and the underlining metal layer. Concurrently, the non-oxidizing surface of the connector 4 presents a low-resistance connection to a spring-loaded wiper arm 6. 
     Accordingly, it may be seen, that there has been provided, in accordance with the present invention an improved electrical connector for an oxidized surface.