US783965A - Commutator. - Google Patents

Description

PATENTED FEB. 28, 1905.

H. A. KNOENBR.

GOMMUTATOR.

APPLICATION FILED JULY 25. 1904.

UNITED STATES Patented February 28, 1905.

PATENT OFFICE.

'HERMANN A. KNOENER, OF EAST ORANGE, NEIV JERSEY, ASSIGNOR TO OROOKER-IVHEELER COMPANY, OF AMPERE, NEW JERSEY, A CORPO- RATION OF NEWV JERSEY.

COMMUTATOR.

SPECIFICATION forming part of Letters Patent No. 783,965, dated February 28, 1905.

Application filed July 25, 1904. Serial No. 218,051.

To all whom, it may concern.-

Be it known that I, HERMANN A. KNOENER, a citizen of the United States of America, and a resident of East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Oommutators, of which the following is a specification.

The object of this invention is to produce a commutator the construction of which is such that structural materials of greater strength and yet of less expensive character may be used and the parts may be more readily and firmly assembled.

The commutator is cylindrical and is provided with commutator-bars such as are ordinarily employed in dynamo-electrical machinery, wherein the commutating-surfaces of the bars form the surface of a cylinder and each bar lies along an element of the cylinder. The ends. of the commutator-bars are clamped between flanges, and the flanges are screwed on reversely-threaded ends of a central tube, thereby holding the bars in place.

Referring to the accompanying sheet of drawingsavhich form a partof this application, Figure 1 is an end ,view of my commutator. Fig. 2 is a longitudinal section on the line H II of Fig. 1. Figs. 3 and 4 are longitudinal sections through the clamping-flanges. Fig. 5 is a side view of the central tube. Fig. 6 is a perspective view of one of the commutatorbars.

The commutator as illustrated in the drawings consists of a series of copper bars A of wedge-shaped section assembled with interposed insulation M, usually mica, so as to form a cylindrical commutating-surface, the bars being parallel to the axis of the cylinder and lying along parallel elements thereof, with the wide edges 0 forming the commutator-surface. The ends of the bars are provided withnotches or V-grooves m. The bars are assembled about a tube or sleeve B. The tube is cut to suitable length from accurately'drawn steel tubing-of regular commercial sizes, which possesses greater tensile strength and costs less than cast-steel requiring to be turned,

which has heretofore been employed in commutator constructions wherein the designs have required that one flange be integral with the sleeve. The ends of the tube are reversely threaded, a right-hand screw-thread 1* being cut on the tube on one end and a lefthand screw-thread 6 being cut on the tube on the other end. Flanges R and L, preferably of bearing metal such as brass or bronze, in the form of nuts tapped with right-hand and left-hand threads, respectively, are screwed on the ends of the tube. Circular ribs t project from the sides of the flanges and are covered with insulating material M, preferably mica. The ribs project into the notches in the ends of the commutator bars, the mica being, however, interposed,and supportthe bars. By reason of the reverse threading of the two flanges they can be tightened simultaneously on the commutator-bars by rotation relatively to the tube in the same direction or preferably by holding both flanges from rotation while the tube is revolved. It therefore follows that the clamping is effected without danger of dragging the commutator-bars and skewing them around at an angle, so that they will be out of parallelism with the axis of the commutator. There is no danger of injuring the interposed mica between the flanges and bars since there is no relative movement between these. Attention is also called to the fact that there is no sliding of contacting surfaces of parts relatively to each other except at the screw-threads, and there is avoidance of all frictional action at a greater distance from the axis than the screw-threads in tightening the parts such as takes place when a nut is screwed against a flange or washer. As

the threads are nearer to the axis, there is less leverage and sliding movement, and the flanges are more readily and mo re li rml y 1t up against the commutator-bars with the application of a given amount of turning force. The tube is notched at Z: to lit over a pin in the armature-shaft on which the commutator is placed.

One end of each commutator-bar is slotted, as shown at w in Figs. Zand 6, for the insertion and soldering therein of connections from screwed on the threaded ends of the tube and clamping the ends of the commutator-bars, 5 and insulating; material interposed between the flanges and the bars, substantially as described.

Signed by me at East Orange, county of Essex. and State of New Jersey, this 16th day 20 of July, 1904.

HERMANN A. KNOENER.

Witnesses:

SAMUEL V. BALoiI,

E. R. DOUGLAS.

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