US1506408A - Commutator - Google Patents

Description

Aug. 26 1924.

E. CLARKE COIIHUTA'I'OR Filed Nov; 23 1921 Q \NVENTOR BY I ATTORNEY Patented Aug. 26, 1924.

UNITED STATES ERNEST CLARKE, on ST. Louis, MISSOURI, WAGNER ELECTRIC CORPORATION,

PATENT OFFICE.

COMIVIUTATOR.

Application filed November 23, 5223..

To all whom it may concern Be it known that I, ERNEST CLARKE, a citizen of the United States 01 America. residing at the city oi St. Louis, State oi Missouri, United States of America, have invented a certain new and useful Commutator, of which the following is such full, clear, and exact description, as will enable any one skilled in the art to which it appertains to make and use the same, refer ence being had to the accompanying drawin s, forming part of this specification,

my invention relates to means for short circuiting a winding of an alternating current motor on the occurrence of predetermined speed or other conditions and part-ioularly to means for mounting and positively retaining in desired position the conducting segments to which the winding leads are connected. These segments are shaped and arranged as in the ordinary commutator and although in the particular embodiment of the invention herein described no brushes are employed, their use in other embodinients of the invention is contemplated and the assembled device will be herein referred to for convenience as a commutator.

One of the ditficulties in the manufacture of commutators arises from the necessity of having each segment firmly held and prop erly insulated from adjacent segments and the fact that the heating of the segments incident to soldering the leads thereto produces strains and other effects which often result in the loosening of segments. It is one object of my invention to provide improved segment supporting and clamping means which will result in a strong, rigid assembly of segments not subject to impair-- ment by the operation of attaching the leads, Other objects are to produce a commutator assembly which can be easily manufactured and at decreased cost of labor and material. One prior art type of commutator assembly over which my invention is intended to be an improvement, is illustrated in Veichsel United States Patent No. 1,214,980.

In the accompanying drawings, Figure 1 is a cross sectional view of a portion of a rotor of a polyphase motor having a commutator assembly embodying my invention, the short circuiting device being in the position which it occupies when the rotor is Serial No. 537, 91.

stationary; Figure 2 is view similar to Figure 1 but showing the short circuiting elements in running position; F i ure 3 is an end view o'l a portion oi? the commutator; and Figure 6' shows a portion oi the split clamping ring for the commutator segments.

1 represents a rotor carrying laminations 2, a permanently short circuited winding and a winding of the commuted type Leads 5 from windin 4: are connected to the commutator segments (3. T represents a steel cup having its outer edge flared outwardly in frusto-conical shape and provided with an inner flange 9 through which the rotor shaft passes and by means of which the cup is supported on the shaft. Seated in the inner portion ot the cup is a cylindrical conducting ring 10. Split wedging ring 11 bears upon the frusto-conical portion of the cup and upon the commutator segments through insulation between the ring and the segments. The cooperating tapered surfaces of the cup and ring cause the ring when pressed into position to firmly press the sides of the wedge shaped commutator segments and the interposed insulation together and form a rigid cylindrical commutator. The lower surfaces of the commutator segments and the inner surface of the conducting ring 10 are in alignment or substantially so when the wedging ring has been pressed into position and the ring is held in position by turning over the outer edge of the cup 7. Exact alignment of inner surfaces of the commutator and ring 10 is produced by malting a finishing cut on a lathe after assembly.

The sleeve 12 slidable on the shaft 1 is actuated toward the position shown in Figure 1 by the coil spring 13. A peripheral groove in this sleeve carries a plurality of short circuiting elements let loosely mounted therein being loosely retained by a wire not shown which passes through holes in the ends of the members.

Upon occurrence of predetermined speed centrifugally operated means, not shown, but which may be of the type illustrated in the lVeichsel patent above referred to, cause the rod 15 to move the sleeve 12 to the left to the position shown in Figure 2 and centrifugal force acting upon the short circuiting members 14 causes them to press firmly upon the segments 6 and the conducting ring tion, said supporting member being provided. 10 thus short circuiting the winding 4 along with a flange to retain the wedging means in a plurality of axes.

The segments (3 are insulated from the ring 10 and from a wedge 11 as shown and preferably the cup 7 is covered with insulation, protecting it from electrical contact with the ends of the coils of the winding 4 and from the leads 5.

It will be apparent that the improved assembly of conducting segments herein shown in an application which constitutes it a multiple point switch, is applicable for use as the connnutator with which brushes cooperate and in any type of machine requiring a commutator. I do not, therefore, intend that the scope of my invention be lim-- ited to the particular application shown.

Having fully described my invention what I claim as new and desire to secure by Letters fatent of the United States is:

l. In a device of the class dei ibed, the combination of an annular supporting member having a tapered inner peripheral sun face, a plurality of segments circularly arranged therein, and means cooperating with the tapered surface of the annular member to hold the segn'ients in position.

2. In a device of the class described, the combination of an annular supporting member, a plurality of segments circularly arranged thcrein, and a split tapered wedging ring cooperating with the inner peripheral surface of the annular member to clamp the segments by motion of the ring longitudinally of the supporting member.

In a device of the class described, the combination of an annular supporting member having a tapered inner peripheral surface, a plurality of wedge-shaped conducting segments circularly arranged within the supporting member, and a wedging ring cooperating with the tapered surface of the supporting member to hold the segments in assembled relation.

4. In a device of the class described, the combination of a supporting member, a plurality of segments circularly arranged, wedging means cooperating with the supporting member to hold the segments in posiwedging position.

5. In a device of the class described, the combination of a cup-shaped supporting member, a plurality of wedge shaped con ducting segments circularly arranged within the supporting member, wedging means between the inner peripheral surface of the supporting member and the segments to hold said segments in assembled relation, the outer edge of the supporting member being bent inwardly to retain the wedging means.

6. In a device of the class described, the combination of a supporting member having a frusto-conical interior surface, a plurality of conducting segments circularly arranged within said supporting member, and wedging means cooperating with the frusto-conical surface and the segn'ients to hold said segments in assembled relation.

7. In a device of the class described, the combination of a cup shaped supporting member having a cylindrical portion and a frusto-conical portion, a cylindrical conducting sleeve within the cylindrical portion of the cup, a plurality of conducting segments circularly arranged within the frusto-conical portion of the cup, and wedging means between said latter portion and the segments.

8. In a device of the class described the combination of a cup shaped supporting member having a frusto-conical interior surface, a plurality of conducting segments circularly arranged within the supporting member with outer surfaces parallel to the axis of the cup, a split wedging ring having its outer surface tapered to correspond with the taper of the frusto-conical surface of the cup, and insulating material between the ring and the segments, the inner surface of the ring being parallel with the axis of the cup and adapted to bear upon said insulatin material to clamp the segments in assembled relation.

In testimony whereof, I have hereunto set my hand and allixed my seal.

ERNEST CLARKE. [L. 5.]

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