US1319751A - Means eor making electrical brushes - Google Patents

Description

O. E. BECKER.

MEANS FOR MAKING ELECTRlCAL BRUSHES.

APPLICATION FILED NOV. 8. 1918.

2 SHEETS-SHEET l- 0. 35. BECKER. MEANS FOR MAKING ELECTRICAL BRUSHES.

APPLICATION FILED NOV. 8. [918.

1,319,751. Patented Oct. 28,1919.

2 SHEETS-SHEET 2.

Jig I70 Original application filedApril 13, 1918,

OLIVER n. I BECKER, o j'oax rank,r 'IgIno I's.

MEA NS ron AKING'ELECTRICAI; nnnsnns.

To all whom it may concern;

Be it known that I, OLIVER E BECKER, a citizen of the United States, residing at Oak Park, inthe county of Cook and State of Illinois, have invented a certain new and useful Improvementin Means for Making Electrical Brushes, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming apart of thls specification. 1

My invention relates tobrushes for electrical machinery and means for making the same. I

. More particularly my invention relates to gauze brushes, that is, brushes made of interwoven or interlaced wires, and means for attaching the leads or pigtails to the same. 7 v

This present application is a division of my co-pending application, Serial Number 228,377, filed April 13, 1918.

As islwell known to those skilled in the fill the parts of the same forholding the form of the brush and for forming a suitably rigid portion for the attachment of the lead or pigtail. A hole is then drilled into the upper part of the brush and the lead or pigtail, which is usually made of stranded cable or woven ribbons, is then andv more frequently,encountered objection is the tendency'of the solder to be taken Specification of Letters Patent.

Patented out. 28,. 1919.

Serial No. 228,377. Divided 'and this applicatior'filed November's, 1918. Serial Na-261 679. r

up by the cableor lead bythe capillary action of the solder upon the :strands' of the cable, thereby-rendering thejlead stiff". If

.the lead becomes filled iwith'solder it bevide mechanism especial-1y arranged "and adapted for practising my improved method ofmakingbrushes and producing :my .improved brush as described and claimed in my said copending application. According to "my invention'I take the brush body after it is v r c ug;;hly formed and compress the same 1nto suitable shape, leaving a, part of the brush .body where the lead is to. be

attached in a relatively loose condition;

I drive a spreading punch in the form of a pointed pin into the imcompressedlpor ion to form a hole, somewhataccording to the manner in wh ch an awl is forced into a. ,piece' of leather or fabric. "The spreading punch preferablydoesnotfform the hole; by shearing or punching, in'the sense of driving themetal downward, but preferably spreads the fibers, and incidentally tearing the same apart laterally. This leaves an enlarged portion in the-body of the brush about the hole. The bodyf'of the brush with the hole formed in the enlarged portion may then gbe dipped to fill" the top. surface with solder so'that the brush may better retain its form. r This latter step may, under certain conditions, be omitted -,Thereafter the lead or pig}-'tail isinserted in the hole and the bodyof the brush about the hole is then crushed together' upon the end of the-lead or pigtail. e

e 'qThe crushing of the body of the brush upon the pigtail causes the individual fibers or Wires of the gauze to gripthe individual fibers of the lead or pigtail very firmly. Thus the intermixing and interlacing of the strands ofthe; wire ,or'gauze on the strands of, the flexible lead,- forms an; ideal ping engagement for holding the. pigtail or lead to; the bo'dy of the brush.

. This [present application; has to; fdo

p i l W th: he. ;n el;,. dies apr e which I have devised for forming the brush, preferably arranged to form the hole for the pigtail inthe same operation which forms the brush.

The brush having been pressed into shape in the dies and the hole formed for the pig tail, a lead is then inserted by hand. The

steps of closing the hole upon the lead and bringing the brush to final form is then performed by another die operation.

Thus not only do I provide a less expensive method of constructing the finished brush, but I provide also an improved and better article and further I provide a convenient means for performing certain steps of the method above outlined. This method may be practised with plain gauze brushes or with the lubricated brush described and claimed in patent to Schweitzer, No. 1,228,484.

My improvement in brush making dies will be more readily understood by reference to said drawings, wherein I have illustrated a preferred form thereof and in which,

Figure 1 is a vertical sectional view taken on the line l1 of Fig. 2 of the die mechanism employed to form the brush;

Fig. 2 is a horizontal sectional view taken on the line 2+2 of Fig. 1, showing certain of the parts in plan;

Fig. 3 is a vertical section taken at right angles to the section of Fig. 1 on line 33 of Fig. 1;

Fig. 4 is an elevational view of the finishing die mechanism;

Fig. 5 is a perspective view of the roll of gauze prior to its formation into rectangular form;

Fig. 6 illustrates the roll of gauze as compressed into rectangular prismatic form, with the hole and enlargement formed at one corner;

Fig. 7 illustrates the body of the brush after the operation of dipping the top of the brush in melted metal;

Fig. 8 is a sectional view of the body of the brush showing the manner of securing the union between the fibers 0f the gauze and the strands of the lead;

Fig. 9 is a perspective view of the body of the brush after the same has been clipped and the pigtail or lead inserted in the hole;

Fig. 10 shows the dies for corrugating the sides of the gauze brush; and

Fig. 11 is a perspective view of a brush with corrugated sides for strengthening the outer layer against spreading.

As previously explained, the first step in producing a brush is to form a roll of gauze by rolling a strip or sheet of the same upon a mandrel to produce a rough roll as shown in Fi 5.

Thi s feature is old and is explained in the prior patents above referred to. The roll of gauze 1, which later forms the body of the brush, is placed in the die mechanism shown in Figs. 1,. 2 and 3 and is there brought to form and is' punched by means of a spreading punch by the mechanism which will now be described. The roll 1 may be given a'preliminary shaping operation before placing in the die mechanism shown in Figs. 1, 2 and 3 or it may be placed in the die mechanism in the rough. In Figs. 1, 2 and 3 I have shown the roll 1 as having a preliminary shaping to bring it to substantially rectangular form, although as above explained this is not a necessity. The roll 1 is rested against a back plate member 2, this back plate being bolted by means of the bolts or cap screws 3 upon the back frame member a, mounted upon the main frame plate 5. The main frame plate 5 in turn is supported upon a suitable pillow block 6 of any desired weight and con 8 and 9 rest against the stops 15 and 16,

which stops are rigidly connected to the main frame plate 5. The retracting rods 17 and 18 are slidably mounted in the blocks 15 and 16 and at their inner ends are threaded to, or otherwise secured to the end die members 8 and 9. Suitable springs 19 and 20 are interposed between the blocks 15 and 16 and the head members 21 and 22 on the rods 17 and 18, so that when the die members are moved inwardly to operate upon the roll of gauze 1, they may be automatically retracted by means of the springs 19 and 20. V

A front die member 23, guided in a suitable frame 24, is adapted to move in and press upon the front side of the roll of gauze 1. A retracting rod or plunger 25 and the spring 26, serve to retract automatically the die member 23, as will be set out below.

A guiding plate 27- extends over the die in the same so that the roll of gauze 1 may spread into the same to form an enlargement. This is forthe purpose of permitting the gauze'to be spreadto form a hole-in thesame for attaching the lead as Will be described later.

,; toward each other when the punch members the roll of gauze is Operated uponby'a 31 and 32 descend.

The front die'member 23 is similarly provided with" an inclined shoulder 38 adapted to be engaged by-the shoulder 39:0'f the vertical cam or punch-member40, which also fastenedinthe lieadmember 33. g I The timing of these punches is suchthat the punch 40 preferably closes in its die member 23- against the body 1 first. The end punches 31 and 32 then close in the end dies S and 9 to compress the roll of gauze 1 into; substantiallyfinished shape and size-with theeXception of the enlarge ment formedin the recesses 28, 29 '.and 30 of the. adjacent die members. -Thereafter spreading punch 42, which consists of-a short pointed pin fastenedin the bar 43.

The bar 43 is in .turn secured by means of p a suitable shank .44 in the head member 33. The roll of gauze 1' is thus transformed into the formed brush body 45, which has" an enlargement 46 to receive the metal of the gauze, which is spread apart or moved laterally" by the formation of the hole 47'. It is to be noted that the opening 47 efitends' only' a short distance down into the body of the brush and also the enlargement 46 eXtends down only a short Way.

Thereafterthe top of the brush body 45 may be dipped in tin or solder to unite the upper strands of the gauze, as indicated at 48 in Fig. 7 Thereafter the stranded lead or pigt-ail 49, the upper end of Which may be attached to a suitable clip 50, is inserted in the opening 47 and the body of the brush with the pigtail or lead 49 in place, is then placed in a suitable closing die 51 and is pressed by the plunger 52 to compress the material of the body of the brush upon the lead 49 and at the same time forming the brush to finished size; It is to be noted that the gauze of the brush may be formed with the fibers thereof running parallel With the edges of the finished brush, or may run diagonal thereto, the resulting brush being securely gripped to the lead, by the mechanical action alone.

It is to be noted that the spreading punch '42 tends t'd spreadiand' maybreak some of the fibers of the-ga'uze-and \vhen'the gauze is compressed about the lead, these ends forineffective gripping fingers for engagingthe strands of the lead 49 so that'a se- I cure fastening is provided.

. I contemplate the use of plain gauze or I lubricated gauze of'thecharacter'set out in tl'ie" prior'patent to Schweitzer above mentioned.

The-body of the brush may be treated as set out in my co-pending application, Serial Number 221,665, filed March 11, 1918, to prevent spreading of the layers of gauze and fraying of'the ends. I have also dis coveredthat the brush may be reinforced by mechanical formation, as shown in Figs.

10 and 11. Bymea'ns'of the die 54 andthe punch 55, indentation's 'orcorrugations 56 maybe formedin thematerial of the brush to provide mechanical reinforcing -ribs.

. This corrugation of the sides may secured at the time that the brush isforme'd in the operations illustrated in Figs. 1, 2,

and 3, .or it'mayibeperformed in a 'closing operation when the material of the brush is compressed about the lead 49 as shown in Fig; 10. 4

I do not intend to be limited to the specific structures herein shown 'an'ddescribed and I intend that certain modifications thereof, such as will be apparent at once to those skilled in the art, shall fall within the scope of the appended claims.

I claim: a -1fAn apparatus for forming a gauze brush of the character described, said apparatus including die members for engaging and compressing theb'ody ofthe 'brush,'s'a1'd members being provided with recesses to 'avoidcompression of the body of-the' brush at the point Where the lead is to be attached.

2. In a die mechanism of the kind descr1bed,'pa1rs of cooperating the members for engaging the lateral sides of the body of a gauze brush, means for moving the dies inpairs into engagement With opposite sides of the brush, said dies having cooperating recesses preventing the compression of the.

brush at the point Where the lead is to be attached.

3. In a die mechanism of the kind described, cooperating flat faced die members for engaging. the lateral sides of a gauze brush, means for relatively moving said members to form and compress the body of a brush, said members having recesses to form an enlargement in the brush at the point Where the lead is to be attached.

4. In a die mechanism of the kind defor engaging the lateral sides of a gauze brush, means for relatively moving said membersto form and compress the body of a brush, said members having recesses to scribed, cooperating flat faced die members form an enlargement in the body of the brush at the point where the lead is to be attached and a pointed spreading punch adapted to be forced into the enlarged part of the brush whil same is held in said die members. v i V 5. In a die mechanism of the kind described, pairs of die members for engaging the lateral sides of a gauze brush, cam means for moving said dies in pairs to form a gauze brush, said dies having cooperating recesses for forming an enlargement on the brush at the point where the lead is to be attached, and a pointed spreader punch adapted to be projected into said enlargement to spread the wires of the brush and form an opening for receiving a lead.

6. The herein described improvement in die mechanism, comprisingdie members for engaging the lateral sides of a gauze brush, means for moving said members in pairs for compressing a brush, said die members provided with cooperating recesses for forming an enlargement on the compressed brush at the point where the lead is to be attached, and means for spreading the wires of the brush at said enlarged part while the brush is held between said die members, for making a hole to receive a lead.

7. In a die mechanism for making gauze brushes, die members for engaging the lat eral sides of a brush, means for moving said dies in pairs into engagement with opposite sides of the brush, said dies having recesses for permittting the formation of an enlargement in the body of the brush as the dies close upon the brush, at the point where the lead is to be attached, a pointed spreading punch attached to said die moving means Copies of this patent may be obtained for five cents each, by addressing the Commissioner and adapted to be thrust into the enlarged part of the brush to providea hole for the insertion of a lead.

8. The herein described improvement in dies for compressing a Wire gauze brush, said dies having cooperating recesses for forming an enlarged uncompressed part in the brush at the point where the lead is to be attached, means for spreading the wires of the brush body at said enlarged part to provide a hole for the reception of a lead wire, and means for compressing the enlarged part to engage a lead inserted in said hole.

9. The herein described improvement in dies for compressing a wire gauze brush, said dies having cooperating recesses for forming anenlarged uncompressed part in the brush at the point where the lead is to be attached, means for spreading the wires of the brush body at said enlarged part to provide a hole for the reception of a lead wire, and transverse ribs on said'dies for corrugating the flat faces of the brush.

10. The herein described improvement in dies for compressing a wire gauze brush, said dies having cooperating recesses for forming'an enlarged uncompressed part in. the brush at the point where the lead isto be attached, means for spreading'the wires of the brush body at said enlarged part to provide a hole for the reception of a lead wire, and transverse ribs o some of said die members for forming transverse grooves in the flat faces of the brush.

In witness whereof, I hereunto subscribe myvname this th day of'Novem'ber, A. D.

OLIVER E. BECKER.

of Patents,

Washington, D. C.

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