Improvements in Current Collectors for Electric, Dynamo, and other Machines.
Year: 1889

page_text: Date of Application, 5th Dec., 1889
Complete Specification Left, 11th Mar., 1890-Accepted, 12th Apr., 1890
PROVISIONAL SPECIFICATION.
Improvements in Current Collectors for Electric, Dynamo, and other
Machines.
I EDWARD HOLT of 1 Chester Street Miles Platting, Manchester in the County of
Lancaster Watch Jobber do hereby declare the nature of this invention to be as
follows:-
My invention relates to collectors or brushes used in electric dynamo and other
machines for collecting the current from the commutator and consists in a novel or
improved arrangement or construction of the same-Ordinarily collectors are formed
of metal blades in contact with the commutator which wear rapidly and cause more
or less sparking in consequence of the high peripherial speed of the commutator.
My improved collector is arranged as follows: - A pair of metal rollers the pivots
of which are mounted moveably so that they can be pressed against and kept in
contact with the commutator by a spring or by springs are placed at opposite sides of
the commutator and are rotated by contact with the same. In contact with the
bosses or pivots of the rollers I arrange spring blades or brushes for taking the
current from the rollers and conducting it to the terminals. By preference I arrange
two spring blades with brass blocks embracing nearly the entire circumference of
one of the bosses or pivots of each roller and apply adjusting devices for keeping the
said blocks in close and easy contact with the boss or pivot of the roller. The
peripherial speed of said bosses or pivots being greatly reduced in comparison with
that of the commutator and the blocks having a large bearing surface upon them
the wear is greatly reduced and sparking avoided by this arrangement.
Dated this 3rd day of December 1889.
EMMOTT & Co.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Current Collectors for Electric, Dynamo, and other
Machines.
I, EDMUND HOLT, of 1 Chester Street, Miles Platting, Manchester, in the County
of Lancaster, Watch Jobber, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to collectors or brushes used in electric dynamo and other
machines for collecting or conducting the current from the commutator and consists
in a novel or improved arrangement or construction of the same. Ordinarily
collectors or brushes are formed of metal blades in contact with the commutator,
which wear rapidly and cause more or less sparking in consequence of the high
peripherial speed of the commutator. The object of my invention is to remedy these
defects which I effect by using metal rollers rotated by contact with the commutator
and metal blades or blocks bearing on the bosses of said rollers for collecting or
conducting the current, the speed of the bosses in sliding frictional contact with the
blades or blocks being thus greatly reduced.
On the sheet of drawings appended hereunto fig. 1 shows an elevation and fig. 2 a
plan partly in section of my improved current collector or conductor.
Upon a boss of the frame a of the machine a rocker b is mounted similarly to the
ordinary rockers. The rocker b is made of a shape similar to that shown on fig. 1
and has fixed to it a stud c upon which a cee shaped spring d is mounted and held
between adjustable collars c¹ c² or their equivalent so that its distance from the

page_text: in
rocker can be adjusted. The ends of the spring d are formed with bosses d¹ d',
which studs or pivots e e are fixed with interposition of insulating washers ff and
bushes gg. Upon the studs or pivots e e metal rollers h h are mounted so that they
can turn freely and the spring d is so bent that it presses the rollers h h against the
commutatork of the dynamo or electric motor and the rollers are rotated by contact.
On the upper ends of the rocker blugs or their equivalents are formed or fixed, to
which thin blades m m insulated from the rocker by non-conducting plates n n are
bolted by screws oo which may form part of the terminals clips p p and are insulated
from the rocker. To the lower part of the blades m m by preference metal blocks rr
are fixed clipping the bosses h¹¹ of the rollers h h as shewn and embracing nearly
the entire circumference of said bosses. Bolts ss are passed through the blades m m
by means of which the blocks rr can be drawn together so as to be in close and easy
contact with the bosses 'h'. The periphereal speed of said bosses being greatly
reduced in comparison with that of the commutator and the blocks having large
bearing surfaces upon the bosses the wear is greatly reduced and sparking avoided by
this arrangement. The current is conducted through the blades m m to the terminals pp
to which the wires conducting to the field magnets coils are attached as usual.
The blocks may be omitted and brushes composed of metal blades bearing
against the bosses ¹¹ substituted for the blades m m, but this arrangement is not so
good as the one shewn on the drawings and herein before described. Instead of the
cce spring d equivalent arrangements for supporting the pivots for the rollers h h
may be used, for instance these pivots may be fixed in swing links suspended on studs
in the upper part of the rocker b and drawn together by a helical spring.
When my improved collector or conveyor is applied to existing machines, the
pivots or equivalent supports of the rollers m m are by preference so arranged that
the axes of the rollers are not in the same plane as the commutator axis but inclined
thereto so that seen from the side the axis of each roller crosses the axis of the
commutator. The line of contact between the roller and commutator thus will not
be parallel to the insulating dividers tt of the commutator, but inclined to it, so that
when a divider crosses the roller the latter is in contact with two of the segments of
the commutator and no interruption of the conducting contact takes place.
The rollers in this case are preferably hollowed on their faces so as to bear on the
commutator on their entire width. In the case of new machines, the rollers are
preferably made cylindrical and their axis placed parallel or in the same plane as the
commutator axis, and the dividers of the commutator arranged inclined, or spirally to
the axis of the same, as shewn on fig. 2 in dotted lines so that in crossing the
dividers the rollers are in contact with two or more segments at once.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is,
Firstly. The arrangement of rocker and current collector or conductor for dynamo
and other electric machines substantially as hereinbefore described and illustrated by
the drawings.
Secondly. In dynamo and other electric machines the arrangement of two rollers
pressed against the commutator by spring pressure and rotated by contact with the
commutator and metal blades with or without bearing blocks in contact with the
bosses or of said rollers for collecting and conducting the current from the commutator
to the field magnets coils, substantially as hereinbefore described and illustrated by
the drawings.
Dated this 10th day of March 1890
EMMOTT & Co.,
Agents for the Applicant.