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Publication numberUS2199532 A
Publication typeGrant
Publication dateMay 7, 1940
Filing dateOct 18, 1938
Priority dateOct 18, 1938
Publication numberUS 2199532 A, US 2199532A, US-A-2199532, US2199532 A, US2199532A
InventorsArthur B Weeks
Original AssigneeArthur B Weeks
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Shunt wire fastener
US 2199532 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Patented May 7, 1940 UNITED STATES PATENT OFFICE 3 Claims.

tive to each other prevented. Therefore, a short circuit due to a loose connection will be prevented and also arcing and resulting damage to the wire or the brush avoided.

10 Another object of the invention is to provide a connection wherein the wire is equipped with a threaded terminal of conductive material which tapers towards its outer end and is screwed into a correspondingly tapered and threaded socket 15 where it will be firmly held against accidental slippage out of the socket.

Another object of the invention is to provide a wire terminal which is expanded as it is engaged with the conductor and frictionally grips 20 the same, thereby causing the terminal to be firmly held in engagement with the conductor as well as being threaded into the socket.

Another object of the invention is to so form the terminal that while it will cause the con- 25 ductor to be firmly secured in a socket against accidental loosening or detachment therefrom, easy removal of the conductor and the terminal from the socket when so desired will be permitted.

Still another object of the invention resides 30 in providing a device which is simple and durable in construction, inexpensive to manufacture and one which will be very eflicient in operation and application to use.

With these and numerous other objects in view,

5 my invention consists in the novel features of construction, combination and arrangement of parts as will be hereinafter referred to and more particularly pointed out in the specification and claims.

The invention is illustrated in the accompanying drawing wherein:

Figure 1 is a view in elevation showing a conductor connected with a carbon brush, the connection being in accordance with the invention.

45 Figure 2 is a fragmentary sectional view showing a portion of the carbon brush with a tapered socket formed therein.

Figure 3 is a group view showing a portion of a twisted-wire conductor and a spring terminal 5 for the conductor in position to be engaged in the socket of the carbon brush.

Figure 4 is a view showing the conductor and its tapered helical terminal anchored in the socket.

55 Figure 5 is a view showing a portion of a carbon brush partially in elevation and partially in section, the sectional portion showing the socket.

Figure 6 is a view showing the brush in section and the walls of the socket threaded.

Figure 7 is a view showing the threaded socket 5 partially filled with cement.

Figure 8 is a view showing an end portion of a conductor thrust into the socket without having a helical terminal applied to it.

Figure 9 is a view showing the conductor en- 10 gaged with threads of the socket and cemented into place.

The subject matter of this invention relates to improved means for securing a shunt wire or conductor I to a carbon brush 2 which in Figure 1 has been shown in operative relation to the commutator 3 of an electric motor or generator, it being understood that the motor or generator will be provided with the usual number of brushes and not merely the one shown. The carbon brush must have the shunt wire firmly connected with it as otherwise a short circuit will result and arcing will occur with resulting damage to the brush and the commutator.

According to this invention, the brush 2 is formed with a socket 4 which is bored therein or formed during molding of, the brush and is tapered towards its inner end as clearly shown in Figure 2. The walls of the socket are formed with threads as shown at 5 and by referring to Figures 3 and 4, it will be seen that these threads are coarse and of arcuate cross section so that they will accommodate the convolutions of, the tapered helical spring 6 which is formed of copper or other conductive material and constitutes a terminal for the shunt wire I. This shunt wire is formed of a plurality of twisted wire strands as shown clearly in Figure 3 and at its extremity the shunt wire is tapered so that it may extend into the terminal 6 for substantially the full length thereof. The tapered helical spring or terminal 6 is of such diameter that it is expanded somewhat as the extremity of the conductor i is forced into it and its contraction about the conductor will cause it to have binding engagement 4,5 therewith and firmly grip the twisted-wire conductor. Solder may then be applied to one or both ends of the helical spring to provide a positive connection between the terminal and the conductor and eliminate any danger of them slipping out of tight binding engagement with each other. After the tapered helical spring has been applied to the conductor, it may be screwed into the socket where the conductor will be firmly held by engagement of the convolutions of the u springinthe threadsoi'thesocket. butsince the terminalisscrewedintothesocket,itmaybe easily removed therefrom if so desired by merely unscrewing it fromthe socket. In view of the fact that the terminal and the socket taper, easy insertion of the terminal may be accomplished by merely thrusting it into the socket and then turning it a few times to elect binding engagement of the terminal in the threads of the socket. This taper also permits easy and quick removal of the conductor and its terminal when so desired. If so desired, the terminal may be fitted into the socket as shown in Figure 3 and the tapered end of the twisted-wire conductor then thrusted into the terminal and turned so that it will be tightly wedged into the terminal and the terminal engaged in the threads of the socket. The positive connection between the conductor and the terminal will be omitted but since the terminal has close fitting binding 8119 about the conductor, accidental slippage of the conductor out of the terminal will be prevented.

In Figures 5 through 9, there has been shown a modified embodiment of the invention wherein the socket has its walls formed with sharp threads as shown at I. It should also be noted that the tapered helical spring terminal is omitted and the end portion of the conductor screwed into the socket for direct engagement with the threads thereof. These threads cut grooves or threads into the strands of the conductor as shown at I when the conductor is thrust into the socket with a twisting movement and threaded engagement will be created between the conductor and the threaded walls of the socket. Before the conductor is screwed into the socket, cement formed of copper dust and a binder is poured into the ductor will be very firmly held in the socket by the combined action of the cement and the threads of the socket and since the cement contains copper dust, a very good electrical connection will be provided between the conductor and the carbon brush. Copper dust cement may also be applied before screwing the terminal I into thesocketifsodesiredandthusinsureagood connection between the conductor and the walls of the socket and in addition a good binding en- Iagement between the terminal and the conductor.

From the foregoing description of the construction of my improved device. the operation thereof and the method of applying the same to use, will be readily understood. It will be seen that I have provided a simple. inexpensive and efiicient means for carrying out the objects of the invention and while I have particularly described the elements best adapted to perform the functions set forth, it is obvious that various changes in form, proportion and in the minor details of construction may be resorted to, without departing from the spirit or sacrificing any of the principles of the invention.

Having thus described the invention, what is claimed is:

1. A carbon brush formed with a socket tapered towards its inner end, a conductor formed of twisted strands, and a terminal consisting of a longitudinally tapered helical coil of conductive metal fitting about an end portion of said conductor and tightly nipp ng the same, said terminal and the portion of the conductor surrounded thereby extending into said socket and held therein by engagement of convolutions of the terminal with walls of the socket.

2. A carbon brush formed with a socket tapered towards its inner end and having its walls formed with threads, a conductor, and a terminal for one end portion of said conductor consisting of a tapered helical coil fitting tightly about the conductor and disposed within the socket with its convolutions engaged in threads of the socket.

3. A carbon brush formed with a socket tapered towards its inner end and having its walls formed with threads arcuate in cross section, a conductor formed of twisted strands, and a terminal for an end portion of said conductor consisting of a tapered helical coil fitting tightly about the conductor in gripping engagement therewith and disposed within the socket with its convolutions engaged in the threads of the socket.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2654038 *Nov 25, 1950Sep 29, 1953Speer Carbon CompanyMolded-in shunt electrical contact member
US2656204 *Nov 10, 1950Oct 20, 1953Frederick W NyquistWire nut
US2790962 *Oct 15, 1953Apr 30, 1957Gen ElectricTerminal assembly
US3056057 *Jun 9, 1958Sep 25, 1962Union Carbide CorpReinforcement of riveted electrical connections
US3056851 *Dec 3, 1959Oct 2, 1962Ideal IndConnector
US3376444 *Sep 13, 1965Apr 2, 1968Carbone CorpCarbon brush assembly
US3646981 *Jun 2, 1970Mar 7, 1972Amerace Esna CorpInsert for sandwich panels
US4152086 *Sep 21, 1977May 1, 1979Wolf-Gerate GmbhTapered connector
US4305588 *Apr 4, 1980Dec 15, 1981Dodge Paul AArchery arrow nock
US4389588 *Mar 24, 1982Jun 21, 1983Alexander RankinCurrent carrying constant force brush holder assembly
US4764579 *Jul 7, 1987Aug 16, 1988The Oakland CorporationPackaged adhesive
US4830624 *Feb 9, 1988May 16, 1989Rose Keith ATwist-on battery connector
US5315066 *Aug 31, 1993May 24, 1994Betts Industries, Inc.Sealed wire connector
US5362250 *Nov 25, 1992Nov 8, 1994Raychem CorporationCoaxial cable connection method and device using oxide inhibiting sealant
US5488261 *May 11, 1994Jan 30, 1996Schunk Kohlenstofftechnik GmbhCarbon brush and fastening a braided indicator wire therein
US5490803 *Nov 8, 1993Feb 13, 1996Raychem CorporationCoaxial cable connection method and device using oxide inhibiting sealant
US5610467 *Jun 30, 1995Mar 11, 1997United Technologies Motor Systems, Inc.Brush holder assembly
US6878880 *Dec 3, 2002Apr 12, 2005Lloyd Herbert King, Jr.Twist-on wire connector
US7129414 *Feb 17, 2005Oct 31, 2006King Jr Lloyd HerbertTwist-on wire connector
US20050139376 *Feb 17, 2005Jun 30, 2005King InnovationTwist-on wire connector
DE2155457A1 *Nov 8, 1971May 17, 1973Hilti AgElektrowerkzeug mit kollektormotor
DE2155457B2 *Nov 8, 1971Jan 15, 1981Hilti Ag, Schaan (Liechtenstein)Title not available
DE2155457C3 *Nov 8, 1971Oct 8, 1981Hilti Ag, 9494 Schaan, LiTitle not available
U.S. Classification310/249, 411/262, 403/372, 439/431, 174/87, 403/268, 439/841, 411/965, 29/826, 403/291, 439/387
International ClassificationH01R39/36, H01R4/22
Cooperative ClassificationY10S411/965, H01R4/22, H01R39/36
European ClassificationH01R39/36, H01R4/22