US1017309A - Brush-holder. - Google Patents

Description

S. H. MORTENSEN.

BRUSH HOLDER.

APPLICATION FILED APR.15, 1909.

P atented Feb.13,1912.

2 SHEETS-SHEET 1.

S. H. MORTENSEN.

BRUSH HOLDER.

APPLICATION FILED APR.15, 1909.

Patented Feb. 13, 1912.

2 SHEETS-SHEET 2.

//////////IIIII/MI////II/////III//I1I V I W Li am m CH. WWW @s/Za 5 45 4 UNITED STATES PATENT OFFICE.

SGREN H. MORTENSEN, OE MILWAUKEE, WISCONSIN, ASSIGNOR TO ALLIS-CI-IALMERS COMPANY, A CORPORATION OF NEW JERSEY.

BRUSH-HOLDER.

Specification of Letters Itatent.

Patented Feb. 13, 1912.

To all whom it may concern:

Be it known that I, SoREN I-I. MORTENSEN, a subject of the King of Denmark, residing at Milwaukee, in the county of Milwaukee and State of W'isconsin have invented certain new and useful Improvements in Brush-Holders, of which the following is a full, clear, and exact specification.

This invention relates to current collecting apparatus, including brush holders and brush holder supports designed particularly for high speed machines such as direct current turbo-generators.

One of the objects of the invention is to provide an effective brush holder having brushes and followers or pressure devices possessing low moments of inertia and high natural periods of vibration so that the brushes will follow very closely the surface of the commutator and sparking will be reduced to a minimum.

A further object is to provide a rigid suporting means for the brush holders which will hold the latter firmly in position and prevent vibration.

The invention may be briefly summarized as consisting in certain novel details of con struction and combinations and arrangements of parts which will be described in the specification and set forth in the appended claims.

Reference is had to the accompanying sheets of drawings, in which- Figure 1 is a side elevation of the current collecting apparatus including the brush holders and supporting means therefor; Fig. 2 is a transverse section taken through the brush ring and yoke and substantially along the lines 2-2 of Fig. 1, looking in the direction indicated by the arrows, a portion of the field yoke being shown in elevation; Fig. 3 is an enlarged side view of one of the brush holders provided with brushes; Fig. 4 is another view of the same looking toward the end of the holder; Fig. 5 is a section taken through the holder substantially along the line 55 of Fig. 3, looking in the direction indicated by the arrow; Fig. -6 is a fragmentary View substantially along the line 6-6 of Fig. 1, looking in the direction indicated by the arrow; and Fig. 7 is an enlarged view of one of the followers or pressure devices employed in connection with each of the brushes.

Referring now to the figures of the drawing wherein I have shown the preferred embodiment of my invention, 10 represents a portion of the field frame or yoke of a high speed machine, and 11 the commutator which is provided with segments surrounded and held in position by spaced retaining rings 12. The brush holders are in this case supported independently of the main frame or yoke of the machine, and for this purpose I have provided as a part of the brush rigging or collecting apparatus, a separate brush yoke 13, which in side elevation is quite similar to the field frame or yoke of the machine and which is supported and secured in position by feet 13 independently of the field yoke. The brush yoke which is divided into two parts for convenience in assembling and handling carries an inner ring 14: which is designed to be adjusted circumferentially relative to the yoke by means of a'handle 15 secured to the ring and extending through a slot 16 in the yoke. The ring may be secured in any desired adjusted position by means of one or more set screws 17 extending through the yoke and engaging a V-shaped groove in the periphery of the ring. Extending inwardly from the ring 1 1 and integral therewith are a number of arms 18 in this case two in number, and arranged diametrically opposite each other, each of the arms 18 supporting a bracket 19 to which brush holders, which will be described presently, are secured. Each bracket has a pair of arms 20 which extend outwardly on opposite sides of the corresponding arm 18 of the ring and are secured thereto by a transverse bolt 21, the arms of the bracket being separated and insulated from the arm of the ring by a U-shaped sheet of insulation 22., shown clearly in Fig. 6. Each of these brackets 19 is also provided with an inner portion 23 which extends longitudinally of the commutator and to which a number of brush holders 24 are bolted, each bracket in this case being designed to have bolted thereto, three brush holders. As will be seen in Fig. 2, the portions 23 of the brackets to which the brush holders are secured are quite close to the surface of the commutator and each of said portions is provided intermediate its ends with a notch 25 in which the middle retaining ring 12 of the commutator rotates,

the brush holders being designed to be secured to each bracket on opposite sides of the notch.

The brush holders 24 are each preferably cast in one integral piece from metal of good conducting material such as brass, and each holder in this case includes a box-like brush receiving or supporting portion 26, also a portion 27 which is bolted to the portion 23 of the bracket and which is connected to the brush receiving portion 26 by a pair of arms 28, and an outer portion 29 which extends over the portion 26 and which carries sleeves forming part of the follower or pressure mechanism, the portion 29 being connected to the inner portions 26 and 27 by means of a pair of arms 30 and 31 which extend inwardly from opposite corners of the portion 29.

In order that the brushes may have small moments of inertia and at the same time large current carrying capacity when taken collectively, each holder is provided with a large number of rather small brushes 32 arranged in two rows, the brushes of one row being inclined relative to the brushes of the other row, so that the inner faces or ends of the brushes will be adjacent. To accom modate these brushes the portion 26 of the holder is divided by longitudinal and trans verse partitions 26 and 26 into a number of sockets, one for each brush. The outer portion 29 of each holder is provided with a number of threaded sockets equal in number to the brush sockets in the portion 26 of the holder, andhaving the same relative arrangement and being axially in line with the sockets for the brushes. Screwed into these threaded sockets are sleeves 33, each provided with an outer knurled head 34, a threaded portion 35, a shoulder 36, and a reduced portion 37 which extends inwardly beyond the portion 29 of the brush holder. The brushes are held yieldingly upon the surface of the commutator by means of rods or plungers 38 and coil springs 39 which surround the rods,'each rod having at one end an enlarged portion 40 provided with a rounded nose or tip 41 which is founed of insulating material and bears upon the outer end of the brush. The coil spring 39 which surrounds each rod bears against the enlarged portion 40 of the rod and the shoulder 36 of the sleeve, the tension of the spring depending, of course, upon the adjusted position of the sleeve 33. In order that the sleeves may be locked in any desired adjusted positions and may be readily released for adjustment, each sleeve is provided with longitudinal grooves or slots 43, which, in this case are located diametrically opposite each other, and the portion 29 of the holder is provided between the sleeves with locking springs tt which are secured by means of screws 45 between the sleeves,

one being provided between each pair of sleeves and having bowed portions which project in the slots of the sleeves so as to normally lock the same against movement, and free end portions which form convenient means for withdrawing the springs from the slots. It will be seen that a follower or pressure device ofthe construction here shown has very little moment of inertia compared with other pressure devices, such as those including pivoted arms which bear upon the brushes, and hence will cause the brushes to follow closely any irregularities on the surface of the commutator.

The brushes of one row of each holder are connected by pig-tails 46 to the portion 27 of the holder and the brushes of the other row are connected by pig-tails 47 to the outer portion 29 of the holder. Inasmuch as the rods 38 are provided at their inner ends with insulating tips which bear upon the brushes, no current can pass through the springs so as to anneal or weaken the same, but will be carried by the pig-tails to the holders or will pass directly from the brushes to the holders.

I do not desire to be confined to the exact details shown and described, but aim in my claims to cover all modifications which do not involve a departure from the spirit and scope of my invention.

l Vhat I claim as new and desire to secure by Letters Patent is:

1. In combination, a brush rigging for a dynamo-electric machine, comprising a yoke independent of the field yoke of the machine, a ring carried by said yoke, said ring having inwardly extending arms, and brackets secured to said arms and insulated therefrom, said brackets having brush holders secured thereto.

2. In combination, in a dynamo-electric machine, a main frame or yoke, a brush rigging comprising a brush yoke independent of the main yoke, a ring supported by said brush yoke, said ring having inwardly projecting arms, a plurality of brush holders, and brackets to which said holders are secured, said brackets having arms whichproject outwardly on opposite sides of the arms on the rings and are rigidly secured thereto.

3. A field frame, a brush yoke supported independently of the fiel'd frame, a ring adjustably mounted on said yoke, said ring having inwardly projecting arms, a plurality of brush holders, and brackets to which said brush holders are bolted, said brackets each having a pair of arms projecting outwardly on opposite sides of one of said arms on the ring, U-shaped sheets of insulation separating the arms of the bracket from the arms of the ring, and bolts passing through said arms and securing the brackets to the ring.

4. In combination, a brush rigging for a dynamo-electric machine, comprising a yoke independent of the field yoke of the machine, a ring rotatable within said yoke, a brush holder mounted on said ring and comprising a brush-receiving portion, an outer brush follower supporting portion, a pair of inwardly projecting arms connecting said follower supporting portion to the brush-receiving portion, said brush-receiving portion having a plurality of brushes, said follower supporting portion having sockets arranged in alinement with the brushes, threaded sleeves in said sockets, and pressure springs between said sleeves and brushes.

5. In combination, a brush rigging for a dynamo-electric machine, comprising a yoke independent of the field yoke of the machine, a ring rotatable within said yoke, a brush holder mounted on said ring and having a frame or body portion with a brush-receiving portion, partitions dividing the same into a number of brush sockets arranged in adjacent rows, a follower supporting portion extending over the brushreceiving portion and connected thereto, brushes in said sockets, said follower supporting portion having threaded socket-s, sleeves mounted in said threaded sockets and having an arrangement corresponding to the arrangement of the brushes and be ing in alinement therewith, and coil springs arranged in the brushes and sleeves.

6. In combination, a brush rigging for a dynamo-electric machine, comprising a yoke independent of the field yoke, a ring movable on said yoke, a brush holder mounted on said ring and comprising a frame or body having a brush receiving portion, longitudinal and transverse partitions dividing the same into brush receiving sockets, brushes in said sockets, a follower supporting portion extending over the brush receiving portion and provided with threaded sockets having an arrangement corresponding to the arrangement of the brush receiving sockets, and being in alinement therewith, sleeves in said threaded sockets, rods extending through said sleeves and having near their inner ends shouldered portions insulated from the receiving portion, longitudinal transverse partitions dividing the same into brush sockets, brushes in said sockets, a follower supporting portion extending over the brush receiving portion and provided with threaded sockets having an arrangement corresponding to the arrangement of the brush receiving sockets, and being in alinement therewith, sleeves in said threaded sockets, rods extending through said sleeves and having near their inner ends shouldered portions insulated from the brushes, coil springs surrounding the rods and bearing against the shouldered portions of the latter and the sleeves, and means for locking the sleeves against movement;

8. In combination, a brush holder comprising a frame or body having a brush receiving portion, partitions dividing the same into a plurality of sockets arranged in two rows, brushes in said sockets, a follower supporting portion connected to the brush receiving portion and extending over the latter, said follower supporting portion being provided with threaded sockets having the same arrangement as, and being in alinement with the brush receiving sockets, adjustable sleeves in said threaded sockets, rods extending through said sleeves and having insulating portions at their inner ends adapted to bear against the brushes, said sleeves and rods having shouldered portions, and coil springs surrounding the rods and engaging the shouldered portions of the sleeves and rods respectively, said sleeves having longitudinal slots and looking springs arranged between the slots and adapted to engage said slots so as to hold the sleeves against accidental movement.

In testimony whereof I affix my signature, in the presence of two witnesses.

soREN H. MORTENSEN.

Witnesses:

II. C. CAsE, CHAS. L. BYRON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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