US983399A - Reciprocating mechanism. - Google Patents

Description

BALS-TON'.

RBCIPROGATING MBGHANISM.

APPLICATION FILED ANLZO, 1907.

Patented Feb. 7, 1911.

s 'sHEIJTs-sHEET 1.

H. H. RALSTON.

BBGIPROGATING MBGHANISM. v

APPLICATION FILED APB..20,1907, 983,399 Patented 1191111911.

3 SHEETS-SHEET 2.

H. H1 RALSTON.

RECIPROGATING MEGHANISM.

APPLIOATION FILED .APB.20, 1907.

983,399. e Patented Fee?, 1911.

3 SHEETS-*SHEET 3.

Cil

UNITED OFFICE.

HOWARD H. RALSTON, OF NORWGOD, OHIO, ASSIGNOR TO. ALLIS-CHALMERS COMPANY, A CORPORATION OF NEW JERSEY, AND THE BULLOCK ELECTRIC lVIANUFACTURINGr .COMPANY, A CORPORATION OF OHIO.

RECIPROCATING MECHANISIVI.

To all ywhom it may concern:

Be it known that I, Howiiuo H. RALs'roN, a citizen of the United States, residing` at Norwood, in the county oli Hamilton and. State ot Ohio, have invented certain new and use't'ul. Improvements in Reciprocating Mechanism, ot which the following is a full, clear, and exact specification.

My invention relates to dynamo-electric machines and particularly to means for imparting an axial reciprocatory movement to the brushes.

It the brushes of a machine are lixed and bear for a considerable time on the same portions of the eommutator or collector rings there a` liability that the commutator or collector rings will become O'rooved or roughened, thus shortening` the liite ot the latter and resulting in sparking and an increase in trictional loss. To overcome this ditliculty it has been proposed to slowly reciprocate the brushes in the direction ot the longitudinal axis of the machines by reciprocating the brush yoke and auxiliary brush supl'iorting members carried thereby. The means generally employed for reciprocating` the brush yokes are those disclosed in the U. patents to Johnson, 788,049, April 535, 1905, and Rambeau, 826,526, July 1T, 1906. As shown in these patents the yokes are slowly reciprocated by imparting1 thereto step by step reciprocatory movements by means of cams and ratchet mechanisms operated from the shalts of the machine.

The object ol my invention is to improve the devices disclosed in the patents above referred to and to provide a novel form ol brush reciproca-ting means which will be et# i'eetive in operation, simple in construction, and inexpensive to manufacture.

In carrying out my invention, I provide means t'or imparting to the brushes an axial reciproeatory movement without reciprocating the yoke. The reciprocatory move ments are preferably imparted to the dilterent brushes or groups of brushes independently, so that it desired, part only of the brushes may be reciiirocated, the positions of the others being fixed, it being unnecessary to reciprocate all the brushes to prevent grooving and roughening of the commutator. The brushes which are not reciprocated are supported in the usual brush forks or other supporting member connect- Specficaton of Letters Patent.

Application filed April 20, 1907.

Patented Feb. 7, 1911.

Serial No. 369,220.

ed to the yoke, and the brushes which are reeiprocated are so mounted as to be mov able relatively to the supporting` members, which may be of special construction. Means are provided on each of said last named brush forks for reciprocating the brushes. A variety of lorms of reciprocating means may be employed, the one here shown comprising ratchet and cam mechas nisms driven or actuated by the rotation of the machine. Also the reciprocating` brush holders may be supported and mounted in a variety of ways.

My invention further consists in certain novel means l'or supporting or mounting, connecting, and reciprocating the brushes and holders, all of which will be more fully described in thev following detailed description.

In the drawings, which show several forms or embodiments of my invention, F igure l is a partial end elevation of a inachine equipped with my invention; Fig. 2 is an enlarged end view showing the reciprocating mechanism; F 3 is a partial side sectional elevation showing a brush fork and attached brush reciprocating mechanism; Fig. 4r is a sectional View along the line Ll-Llol Fig. 3; Fig. 5 is a detail of a portion ot the brush reciprocating mechanism; Fig. 6 is a` view similar to Fig. 3 showing` a modiication; Fig. T is a sect-ion along the line 7-7 of Fig. 6; Fig. 8 is a view similar to Figs. and G showing a 'further modilication; and Fig. 9 is a section along the line 9 9 ot Fig. S.

Referring tirst to Figs. 1, Q, 3, l and 5 ot the drawings, 10 indicates the field yoke, ll the armature, and l2 the commutator 01" a direct current dynamo-elcctrie machine equipped. with my invention. Supported on rollers 13 on the side oi the lield iframe is ay brush yoke 1st ot the usual construction. Mounted on the brush yoke are ordinary brush forks l5 having brushes and holders 1G which are fixed in position and forks 15 which carry brushes and holders 1Ga adapted to be reciprocated. The ratio of fixed and reciprocatingl brushes can be made anything desired and can l e varied by substituting` one form of fork for the other. In Fig. l the brushes and holders supported hy every third brush itork are adapted to be reciprocated. The brushes and holders 1G are so mounted as to be axially movable relatively to the forks 15a, the latter being provided with reciprocating devices or mechanisms which are preferably actuated independently and successively by the rotary member. ln the embodiment of my invention here shown the reciprocatory brush holders are secured to studs 17 which have a sliding tit in the ends of the brush forks 15a and are adapted to be reciprocated therein. r1`he inner ends of the studs and openings in the inner arms of the forks are preferably cylindrical for convenience in construction. The outer ends of the studs and openings in the outer brush forks may be so shaped as to prevent the studs from turning in the brush forks, or the studs or forks may be provided with keys or splines 18 for this purpose. As here shown the outer arms of the forks are split and the pressure of the bearings on the stud can be adjusted by screws 19. In this instance each stud 17 is adapted to be reciprocated by a separate ratchet mechanism and cam mounted on the brush fork. Mounted on a pin or stud on the outer arm of each brush fork 15a is a rotary member forming part of said mechanism having a disk Q0 toothed or notched on its periphery and a hub Q1 having a cam slot 21a engaged'by a pin, screw or other projection Q2 on the outer end of the stud 17. The disk and cam are adapted to be rotated b v a pawl comprising` a verticalljvv movable rod supported on a pair of arms 2st and 21H extendingl outwardly from the brush fork, said rod having a finger 25 with a pivoted or hinged nose 25 adapted to engage the teeth of the disk. and on its lower end a roller or wheel 2G. The rod is adapted to move freely in the arms 24; and 24a, the downward movement being` limited by a block QT adjustably secured to the upper end of the rod above the arm Qt and adapted to engage the upper face of said arm. A pin Q8 secured to the arm passes through the block QT and serves as a guide for the pawl. A spring 29 on the rod between the arm Q4 and the finger holds the rod normally in its innermost position. The end of the spring bears on the nose 25 to hold the latter in position to engage the teeth of the disk Q0 when the rod is moved outward. The ratchet. mechanism on each fork 15a is adapted to be operated in this instance by one or more shoes 30 (one beingl here shown) adjustably secured to the end of the commutator by screws 31, in such a position as to engage the roller QG and lift the rod Q3 when the armature and comn'iutator are rotated. The outer face of the shoe is curved as shown and is preferably covered by some comparatively soft material such as leather to reduce to a minimum the shock and noise of contact with the rollers. To provide paths of low resistance between the brushes and holders which are reciprocatcd and the corresponding brush forks, I connect all the holders mounted on each stud 1T to the fork 15L by a low resistance flexible conductor 32. As is shown, the conductor 32 is secured to the top of each brush holder by a screw 33 and is secured at one end to the fork by being clamped by one or more screws 34- in a slot in the arm of the fork. The brushes are electrically connected to thc holders and to the conductor 32 by tlexiw ble shunts or pig-tails 36 the end of the shunts being preferably clamped to the coni ductor 32 by the screws The use of this conductor 39. connecting the ln'ush-holders and fork is not confined to holders which are reciprocated relatively to a fork. but may be used with advantage when the brushes are fixed, as the bearing surfaces between the holders and studs, and studsl and forks are sometimes small. lVhen the machine is in operation. the shoe 30 mounted on the face of the armature engages successively the rollers QG of the reciprocating mechanisms on the brush forks 1511. Each roller is in turn lifted a distance depending upon the adjusted positions of the shoe and roller. rotating the notched disk Q0 and the cam slotted hub 21, and thus slowly reciprocating step-by-step the studs 17 on which the brushes and holders 1Gn are mounted. The period of reciprocation can be varied by adjusting either the position of the shoe 30 or the positions of the vertically movable rod Q3 and rollers 2G, or by varying the number of shoes BO employed. lf desired. different rates of reciprocation can at the same time be imparted to the different groups of brushes by so adjusting the normal positions of the rods and rollers that the movements of the rods and arcsl through which the notched disks are moved at each rotation are different.

rts stated before. the particular .supports or mountings for the reciprocatory brushes and holders may be widely varied. ln the niodiiication shown in Figs. (S and 'l' the brush stud is fixed in the brush forks 15] and the brushes and brush holders are mounted on a sleeve 23T which has a sliding i'it on the brush stud and is adapted to be reciprocated by mechanism similar to that previously described. V[n this case the notched or toothed disk and member 38 having a cam slot- 3Sil are mounted on a pin or spindle passing through the outer arm of the brush fork, the member 3S being located on the inside of the arm. The sleeve 37 is provided with a pin, screw or other projection 39 which engages the 'cam slot 38: The reciprocatingmechanism is otherwisc the same as that first described. Then the machine is in operation the ratchet and cam are actuated, slowly reciprocating the sleeve 3T and the brushes and holders carried thereby. The brush holders are conl OO nected to the brush fork as in the firstinstance by a flexible conductor 40.

In 8 and 9 I have shown a still further moditication. In this case the brush holders have a sliding' lit, on the brush stud, which is `fixed in the brush iork 15C as in the construction last described. As here shown the brush holders are secured together by a rigid bar -l-l preferably of conducting` material, one end of which bar is provided with a lug or projection l2 which engages the cani slot l-lb oit' a rotary member 44: arranged and actuated as in the case last. described. The other end ot bar Il extends upward and is connected to one end of a tlexible conductor lo the other end of which is clamped or otherwise secured to the brush fork. Thus when the armature and comnnitator are rotated the ratchet and cam mechanism is actuated, slowly reciprocating,` the bar il and the brush holders attached thereto.

It will be seen that the details can be modified considerably without departingfrom the spirit and scope of my invention and I aim in my claims to cover all such modifications.

IVhat I claim as new and desire to secure by Letters Patent is l. In a dynamo-electric machine, a plurality ot lixed brushes, aI plurality of movable brushes, and means for imparting an axial reciprocatory movement to said movable brushes.

In a dynamo-electric machine, a brush yoke, a brush supporting' member secured to said yoke, a group of brushes, and means carried by said brush supporting member for imparting an axial reciprocatory movement to the brushes independently of the yoke.

In a dynamo-electric machine, a brush yoke, a` 'plurality of brush supporting members secured thereto, brushes supported by said members, and means carried by one or more ot said members for imparting an axial reciprocatory movement. to the brushes supported thereby independently of the yoke.

4. In a dynamo-electric machine, a brush yoke, a plurality ot brush supporting members secured thereto, a plurality of relatively fixed brushes carried by some of said members, a plurality of brushes mounted for movement in the direction of the axis of the machine and carried by other of said members, and means carried by said last named brush supporting members for impart-ing` an axial reciprocatory movement to said movable brushes.

In a dynamo-electric machine, a brush yoke, a brush fork, a plurality of brushes and holders supported by said fork and mo'able relatively thereto in an axial direction, means carried by said fork it'or imparting an axial reciprocatory movement to said brushes independently or' the yoke, and means for operating said tirst named means by the rotation ot the machine.

In dynamo-electric machine, a brush yoke, a brush simportingmember secured thereto, a plurality of brushes and holders carried by said member, and means carried by said member for imparting to said brushes and holders an axial reciprocatory movement independently of the yoke, said means comprising` a rotary cam member.

7. In a dynamo-electric machine, a brush yoke, a brush fork, a brush stud carried by said fork, a brush and holder carried by said stud, and means dependent upon the operation of the machine for moving said brush and holder axially et' the machine and relatively to the brush i'ork.

8. In a dynamo-electric machine, a brush yoke, a brush fork, a brush stud carried by said lork, a plurality of brushes and holders mounted on said stud, and means dependent upon the operation ot the machine for moving said brushes and holders axially ot the machine and relatively to said fork.

9. In a. dyna1m electric machine, a brush yoke, a brush fork, a brush stud carried by said fork, a brush and holder mounted on said stud and movable relatively to said fork, and means for reciprocating` said brush and holder.

10. In a dynamo-electric machine, the combination of the commutator, a plurality of brushes cooperating therewith, and means for automatically moving less than all of the said brushes relatively both to the commutator and to the remainder ot' said brushes.

l1. In a dynamoelectric machine, the combination ot' a conunutator, a plurality of brushes cooperating therewith, and means for automatically moving less than all of said brushes axially of the commutator and relatively to the remainder of said brushes.

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

I-IOIVARD II. RALSTON.

IVitnesses GEO. B. SoiiLnx, FRED J'. KINsnx.

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