close

Вход

Забыли?

вход по аккаунту

?

Патент USA US2870358

код для вставки
janîzo,
I
HIGH
E. 1_ ALTITUDE
SHOBERT
BRUSH
l1.
Filed April 9, 1956
, f/
Fig. Ö
y//5\
déb
d
Pig. 4
INVENTOR.
¿WF Á ¿Haai/@riz
BY
¿ab? ÜMW/
United States Patent C ” ice>
2,370,353
Patented Jan. 20, 1959
2
Fig. 2~is a similar viewv after the brushes have been`
worn considerably;
Figs. 3 and 4 are views of the contact face of a-brush
2,870,353'`
as seen in Figs. 1 and 2, respectively; and
Fig. 5 is a perspective viewof a modification.
Referring to Figs. l and 3` of the drawing, a rotating
current-collecting ring 1 is shown, which can be a slip
HIGH ALTITUDE BRUSH
Erle I. Shobert II, St. Marys, Pa., assignor to Stackpole
Carbon Company, St. Marys, Pa., a corporation of
ring> or a commutator of a dynamoelectric machine. En
Pennsylvania
gaging thisring is a pair of carbon brushes. These
brushes will usually be just alike, so only one will be de
scribed. The body 2 of the brush is a rectangular block
Appiication April 9, 1956, Serial No. 577,136
4 C_laims._ (Cl. 3110-228)
This invention relates to carbon brushes for dynamo
electric machines that-aroused at high altitudes.
It iswell known that the carbon‘brushes of electric
motors and generators used in airplanesilying at high alti
tudes wear away very rapidly unless they are specially
treated to prolong their usefulness. The brushes have 20
been treated in various Ways to incorporate in them cer
tain compounds, called adjuvants, that have been found to
be etfective. Adjuvants that have been used include lith
ium carbonate, molybdenum disulfide, and many non-hy
droscopic metallic halide salts. These adjuvants have
been mixed with the basic carbon mixtures, they have
been impregnated in the brushes, they have been coated
of carbon, the width of which generally is substantially
coextensive with the width of the adjoining. ring.. They
thickness of the brush ,circumferentially of the ring can
be any desired amount, which is also true of the length
or height of the brush. The body of the brush is- pro
vided with two or more substantially parallel openings
3, which extend from its contact face outwardly toward
its outer end. These openings are ñlled with the adjuvant
4 that it is desired to use in the brush. The particular
adjuvant used is not important as far as this invention
is concerned, but whatever material is used, it will tend
to form a ñlm o-n the collecting ring and will wear the
ring either more or less than does the rest of the brush.
25 The brush openings, with their inserts of adjuvant, are
spaced apart in a direction across the width of the brush;
that is, the openings lie in a projected radial plane of
the ring.
it is a feature of this invention that the openings and
and laterally spaced openings in the brush faces.
All of these brushes, except the type mentioned last, 30 adjuvant inserts are not perpendicular to the surface of
the adjoining collecting ring, but are inclined to it. They
will wear the adjoining commutator or slip ring uniform
all lean in the same direction in the radial plane of the
ly, but they have the disadvantage that the adjuvants
onto the sides of the brushes and they have filled slots
sometimes build up films on the current-collecting mem
bers that are so thick that they affect commutation ad
ring mentioned in the preceding paragraph. Consequent
ly, as the brush wears away, the areas of contact of the
adjuvant inserts with the ring will move across the ring
because, as the inserts are shortened, their exposed ends
recede from one end of the brush and approach the op
cores of adjuvant, the ends of which are exposed at spaced
posite end. This can be seen by comparing Figs. l and 3
intervals along the face of the brush. With such a brush,
with Figs. 2 and 4, which show the brush after it has
the portions between the cores are untreated and can
therefore exert the influence of an untreated brush on 40 been worn considerably. Due to this gradual shifting
of the areas of contact between the adjuvant and the ring
machine performance because thick commutating films
from one side of the ring toward the other side, grooves
will not be built up in these untreated areas. Neverthe
will not be worn in the ring. instead, the wear will
less, another~ disadvantage arises, which is due to the
progress slowly across the ring. It also will be reduced,
difference in wear of the current-collecting ring because
of the fact that the cores and the basic brush material 45 because neither the inserts nor the brush body between
them are permitted to continue their iniluence along only
do not have the same Wear characteristics. ln other
one band on the ring.
words, grooves are worn around the ring. This uneven
In order to distribute the wear nearly uniformly over
ness of Wear can become so pronounced that in some cases
versely. This disadvantage is practically eliminated where
the brush is provided with a plurality of laterally spaced
substantially the entire area of the ring, the adjuvant
it is unsafe to replace brushes without first machining
50 inserts should be provided in such number and at such an
the ring.
inclination to the ring that, before the brush becomes
It is among the objects of this invention to provide a
brush, which includes an adjuvant but which Wears the
current-collecting ring uniformly without overfilming its
surface.
Accordingly, the carbon body of the brush is provided
with a plurality of substantially parallel openings which
worn so much as to have to be replaced, the area of
Contact between each insert and the ring will have moved
from its original position to a point where it will engage
or overlap the area where the next insert originally en
gaged the ring.
This can be done by inclining each
insert at such an angle that its outer end will overlap
the inner end of the next insert, as shown in Fig. l. ln
other words, the inner end of each opening 3 or insert
extend from the contact surface of the brush towards the
opposite end of the brush. These openings are filled with
the desired adjuvant. They are spaced apart in a direc 60 of adjuvant and the outer end of the opening beside it
tion across the width of the brush and are inclined in
will both intersect a common transverse plane of the
that direction. Consequently, as the brush Wears away,
brush, which is perpendicular to the contact face of the
the areas of Contact of the inserts of adjuvant with the
brush.
current-collecting ring will move across the ring, resulting
It is not necessary that only the inner ends of the ad
in distributing the wear under the inserts and the inter 65 juvant inserts be exposed, for, as shown in Fig. 5, a side
vening brush body over substantially the entire area of
of each adjuvant-receiving opening 6 may be open so that
the ring.
The preferred embodiment of the invention is illustrated
in the accompanying drawings7 in which
the adjuvant 7 therein will be exposed. This happens
when the openings are formed as slots in one or both
sides of the brush body 8. The depth of the slots can
Fig. l is a side view of my brush engaging a rotating 70 be any desired amount, and they may even extend en
tirely through the brush.
current-collecting member, with one brush shown in sec
l10n;
According to the provisions of the patent statutes, I
3
2,870,353
have explained the principle of my invention and have Y
illustrated and described what I now consider to represent
its best embodiment. However, I desire to have it under
stood that, within the scope of the appended claims, the
invention may be practiced otherwise than as specifically
illustrated and described.
I claim:
1. A dynamoelectric brush having at one end a contact
face`adapted’to engage a rotating current-collecting ring,
the brush comprising a carbon body provided with a 10
plurality of substantially parallel openings extending from
said face toward the opposite end of the brush, and an
adjuvant filling the openings, said openings being spaced
4
t
adjuvant ñlling the openings, said openings being spaced
apart in a direction across the width of the brush and
being inclined in that direction to such an extent that the
inner end of an opening and the outer end of the next
opening will both intersect a common transverse plane of
the brush perpendicular to said contact face; whereby,
as the brush wears away, the areas of contact of said
adjuvant with the current-collecting ring will move across
the ring.
'
.
»
3. A brush according to claim 1, in which said openings
are open only at said contact face.
4. A brush according to claim l, in which a side of
each of said openings is open.
apart in a direction across the width of the brush and
being inclined in that direction; whereby, as the brush 15
wears away, the areas of contact of said adjuvant with
the current collecting ring will move across the ring.
2. A dynamoelectric brush having at one end a contact
References Cited in the ñle of this patent
UNITED STATES PATENTS
427,674
2,736,830
face adapted to engage a rotating current-collecting ring,
the brush comprising a carbon body provided with a 20
plurality of substantially parallel openings extending from
said face toward the opposite end of the brush, and an
115,704
646,778
Daft ________________ __ May 13, 1890
Savage _______________ __ Feb. 28, 1956
FOREIGN PATENTS
Austria ______________ __ Jan. 10, 1930
Germany ____________ __ June 21, 1937
Документ
Категория
Без категории
Просмотров
0
Размер файла
263 Кб
Теги
1/--страниц
Пожаловаться на содержимое документа