IMPROVEMENTS IN OR CONNECTED WITH THE COMMUTATORS OR COLLECTORS OF ELECTRICAL MACHINES
Year: 1884

page_text: I JOHN HENRY JOHNSON of 47 Lincolns Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of said Invention for "IMPROVEMENTS
IN OR CONNECTED WITH THE COMMUTATORS OR COLLECTORS OF ELECTRICAL
MACHINES" a communication to me from abroad by Zenobe Theophile Gramme.of
Paris in the Republic of France to be as follows:-
This Invention relates to Dynamo electric and Electro dynamo machines and
consists in a combination of devices hereinafter described for operating the
Commutator brushes or rubbers by causing the brush holders or carriers to oscillate
simultaneously upon supports arranged as hereinafter explained In place of an
oscillating motion the brush holders may be caused to partake of any other
equivalent motion towards or from the Commutator.
When it is desired to operate a number of brushes simultaneously, they have
usually been placed upon a single support or carrier which is caused to turn upon
the axis of the Commutator but this arrangement renders the adjustment difficult
and an equal pressure of all the brushes impossible in practice.
According to the present invention the support of the brushes is stationary and
all the brush holders are operated simultaneously by the intervention of accessory
appliances arranged as hereinafter described.
In carrying out the said Invention as applied to a dynamo Electric machine for
example presenting say six poles the three positive brushes are carried by suitable
brush holders connected by studs or pivots to a stationary disc or support and the
three negative brushes are similarly carried by three other holders connected in
like manner to another disc or support also fixed or stationary. A star shaped
plate carries a series of pins which engage with corresponding recesses provided in
the extremities of the brush holders. By suitable means such as by a lever the
star shaped plate may be caused to turn on its centre which preferably coincides
with the axis of the machine and thereby operate all the brushes simultaneously
so as to place them in or out of contact with the Commutator and adjust their
pressure with great precision.

page_text: In place of pivotting the two sets of brush holders upon the two separate discs
all the said brush holders may be carried by a single disc provided that they are
suitably insulated. If preferred the disc or discs may be dispensed with the brush
holders being supported directly by the frame of the machine. The star shaped
plate by which the brushes were operated in the arrangement hereinbefore described
may be stationary the discs carrying the brushes being caused to move upon their
axes relatively to the said plate instead of causing this plate to move relatively
to the discs. In place of the pins on the plate herein before described tappets cogs
or other equivalent devices may be employed to impart the requisite motion to the
brushes or collectors.
In the case of a machine having say twelve or other large number of poles the
series of positive brushes is preferably carried by one disc and the negative brushes
are carried by another disc.
These two discs are screwed or rigidly connected together and to a third disc or
ring capable of turning on a support arranged concentrically to the shaft of the
machine. This ring and the two discs carrying the brushes, are insulated
electrically-Pins which operate the positive brushes are carried by one annular
plate and the pins which operate the negative brushes are carried by another
annular plate. These two plates are screwed or rigidly connected together and to a
ring preferably arranged at the side and on the same support as the ring connected
to the discs carrying the brushes-This ring and the annular plates connected
thereto are insulated..
By means of an endless screw or worm gearing with a rack or segment of a
worn wheel connected to the annular plates carrying the pins for operating the
brushes; these plates may be turned to the right or to the left and thereby take off
or put on and adjust the pressure of thelbrushes which collect the current from the
commutator.
The position of the brushes relatively to the polar axes is first adjusted by
calising the discs carrying the brushes to turn on the axis of the machine' anl
securing them in the proper position by means ofta bolt working in a slot in. a
fixed plate When this bolt is removed the brushes may be turned completely
round on their support for the purpose of adjusting them accurately to the required
length This may be done with great precision by bringing each brush.in turn
opposite a fixed nick, or mark and causing the carrier to describe exactly one twelfth
of a revolution at a time.
111
تيمم
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page_text: "
I JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention for "IMPROVEMENTS
IN OR CONNECTED WITH THE COMMUTATORS OR COLLECTORS OF ELECTRICAL
MACHINES which. Invention has been communicated to me from abroad by
Zenobe Theophile Gramme a person resident at Paris in the Republic of France
and in what manner the same is to be. performed to be particularly described
and ascertained in and by the following statement:―
This Invention relates to the commutators or collectors of Electrical apparatus
such as magneto and dynamo electrical machines and it consists in a combination
of devices for throwing all the brushes in and out of action simultaneously and at
the same time enabling the amount of friction between the said brushes or rubbers
and the commutator segments to be regulated with great facility and precision.
These results are obtained according to this Invention by connecting all the brush
holders to a central plate or ring whereby they are enabled to be simultaneously
shifted or adjusted upon the support or supports carrying the said brushes as
hereinafter explained.
When it is desired to operate a number of brushes simultaneously they have
usually been placed upon a single support or carrier which is caused to turn upon
the axis of the commutator but this arrangement renders the adjustment of the
distances difficult and the obtainment of an equal pressure of all the brushes
impossible in practice.
According to the present invention the support of the brushes is preferably
stationary and all the brush holders are operated simultaneously by the inter-
vention of accessory appliances arranged as hereinafter described.
And in order that the said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the corresponding figures.
Figure 1 of the accompanying drawings represents the arrangement of parts for
operating commutator brushes or collectors according to this Invention as applied
to a machine with six brushes.
Figure 2 represents a vertical section of an equivalent arrangement applicable to
a machine with twelve brushes.
Figure 3 is a plan and
Figure 4 an end elevation of the same.
In carrying out the said Invention as applied to a dynamo electric machine for
example presenting six poles as in the arrangement illustrated in Figure 1 the
three positive brushes indicated at J are carried by suitable brush holders C
pivotted at c to a stationary disc or annular support A and the three negative
brushes indicated at J' are similarly carried by corresponding holders C¹ pivotted
at c' on a disc or support B also fixed or stationary. A star shaped plate E carries
a series of pins e e¹ which engage respectively with corresponding recesses provided
in the extremities of the brush holders C and C. By means of a lever L attached
to the star shaped plate E the latter may be caused to turn on its centre which
preferably coincides with the axis of the machine and thereby be caused to operate
all the six brushes simultaneously so as to place them in or out of contact with the
commutator K and adjust their pressure with great precision.

page_text: .
Figures 2, 3 and 4 show the application of the same principle of adjustment to a
machine with twelve brushes. A is an insulated annular plate or ring carrying six
positive brush holders J the six negative holders J¹ being carried by a similar
insulated plate B. The plate A is connected to the plate B by insulated screws L
figure 2 and to a ring E by insulated screws M. The ring E is concentric with the
shaft of the machine (indicated at O) and is capable of turning upon a support P
formed on the bearing of the shaft. The brush holders J J₁ are capable of
oscillating upon pins R by which they are connected to their respective plates A
and B and the plate A is provided-with an arm A¹ carrying a worm G operated by
a hand wheel G¹ and engaging with a corresponding toothed segment S (shewn by
dotted lines in figures 2 and 4) connected to an insulated annular plate or ring C
connected by insulated screws L¹ to a similar insulated plate or ring D. The
plate C carries pins e which operate the positive brush holders J and the plate D
carries similar pins e¹ for operating the negative brush bolders J'. 'Insulated
screws M¹ connect the plate D to a ring F capable of turning upon the same
support P as the ring E.
.
The position, of the brushes relatively to the polar axis is adjusted in the first
instance by means of a screw X working in a curved slot in a support. H fixed to
the bearing of the shaft. By removing this screw the whole of the plates or rings
connected with the brush holders may be turned upon the support P thus affording
facilities for accurately adjusting the length of the brushes by.causing the said
rings to describe one twelfth of a revolution at a time so as to bring the ends of
the brushes in succession opposite. a stationary mark.or stop. This preliminary
adjustment having been effected and the supports of the brush holders or plates A
and B having been fixed in the proper position by means. of the screw X the
pressure of the brushes upon the commutator segments (indicated at K) is.regulated
with precision by turning the worm G and thereby causing the annular plates. or
rings C, D, and E,to,turn upon the support P. These.plates.being connected to the
brush, holders, as hereinbefore described the latter are caused to press with a readily
regulated degree of pressure upon the commutator K or are moved entirely out, of
contact with the commutator according to the direction in which the screw G.is
turned and the amount of angular displacement of the plates C and D.produced by
the action of the said screw.
In place of pivotting the two sets of brush holders upon the two separate discs
or supports A and B respectively all the said brush holders may be carried by a
single support provided that they be suitably, insulated. If preferred the supports
may be dispensed with the brush holders being attached directly to the frame.of
the machine and the brush holders may partake of a sliding or other equivalent
motion in place of the oscillating motion hereinbefore. described.
上
The plate or ring by which the brushes are operated in the arrangement
herein before, described with reference to figure 1 may be stationary the supports
carrying the brushes being caused to move upon their axis relatively.to.the said
plate instead of causing this plate to move relatively to the: supports and in place
of the pins hereinbefore described for imparting motion to the brush holders,
tappets, cogs or other equivalent devices may evidently be employed to impart the
requisite motion to the brushes or collectors without departing from the principle
of the Invention.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is, to be performed I declare. that..what
I claim is
First-In the commutators or collectors of electrical machines pivotting or
centering the. brushes or rubbers upon a support or supports and operating all the
brushes or rubbers simultaneously by changing the relative position of the said
support and of plates or rings (connected to the brush-holders) by a partial rotary
or angular motion substantially as herein before described and illustrated in the
accompanying drawings.

page_text: Second-The combination and arrangement of parts constituting the com-
mutator or collector for electrical machines substantially as hereinbefore described
with reference to figure 1 of the accompanying drawings.
Third-The combination and arrangement of parts constituting the commutator
or collector for electrical machines substantially as hereinbefore described with
reference to figures 23 and 4 of the accompanying drawings.
J. HENRY JOHNSON,
47, Lincoln's Inn Fields, London, W.C.