Apparatus for Operating and Locking the Brushes of Dynamo Electric Machines.
Year: 1888

page_text: Date of Application, 9th May, 1888
Complete Specification Left, 7th Mar., 1889
Complete Specification Accepted, 13th Apr., 1889
PROVISIONAL SPECIFICATION.
Apparatus for Operating and Locking the Brushes of Dynamo
Electric Machines.
I, EDWARD JOHN HOUGHTON of 1 Pilkington Road, Peckham, London, S.E.
do hereby declare the nature of this invention to be as follows :-
When working dynamo machines it is in some cases desirable for their brushes
to be brought into operation by means of electro magnets and locked when either
on or off as the case may be In the electric lighting of Railway trains for example
where separate sets of brushes are used for "Up" and "Down" running it is
necessary that one set should be locked or prevented touching the commutator
when the other set is at work-I do this by attaching the armature of an electro
magnet to each set of brushes in such a manner that when either electro magnet
is brought into operation that set of brushes to which its armature is attached is
brought to bear on the dynamo commutator-At the same time the other electro
magnet is locked so that the brushes to which it is fixed are prevented from touching
the commutator-When neither set of brushes is required to be used both electro
magnets are locked-A current passing through the electro magnets unlocks their
armatures-When they are unexcited the armatures are locked.
Doted this 8th das of Mar 18AA
E. J. HOUGHTON.

page_text: COMPLETE SPECIFICATION.
Apparatus for Operating and Locking the Brushes of Dynamo-
electric Machines.
I, EDWARD JOHN HOUGHTON of 1 Pilkington Road, Peckham, London S.E.
Electrical Engineer, 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 :-
When working dynamo-machines it is in some cases desirable for their brushes to
be brought into operation by means of electro-magnets, and locked when either on
or off, as the case may be." In the electric lighting of railway trains, for example,
where separate sets of brushes are used for "Up and Down" running, it is necessary
that one set should be locked or prevented from touching the commutator when the
other set is at work. I do this by attaching the armature of an electro magnet to
each set of brushes in such a manner that when either electro-magnet is brought into
operation that set of brushes to which its armature is attached is brought to bear
on the dynamo-commutator. At the same time the armature of the other electro
magnet is locked so that the brushes to which it is fixed are prevented from touching
the commutator. When neither set of brushes is required to be used both armatures
are locked.
A current passing through the electro-magnets unlocks their armatures.
When they are unexcited the armatures are locked.
The accompanying drawing shews a diagrammatic view of an arrangement for
carrying out my above described invention. A is the commutator of the dynamo
machine, B B B B¹ are the two sets of brushes, carried in a rocking frame H H
mounted on centres at I I, so that when the frame is inclined to the left, the
brushes B B will come in contact, while B¹ B₁ come in contact when the frame is
inclined to the right.
Care electro magnets having armatures D) D¹ which are attached to a fixed
point at the one end, and at the other end are connected respectively to each side
of the rocking frame, so that on the armature D being attracted by its electro magnet,
it will move the frame H so as to bring the brushes B B into action, while the
brushes B B will be brought into action aud B B be put out of action if the
armature D' is attracted.
The coils of the electro magnets CC¹are connected to the shunt circuit of the
dynamo machine by means of a suitable contact device such for example as that
described in the Specification to Patent No. 155974, whereby when the dynamo is
travelling in one direction, only one of the electro magnets is put in circuit with it, and
when it is travelling in the contrary direction the other electro magnet is put in circuit.
The electro-magnets C C have other small soft iron armatures F F₁ which are
situated near to the core of one of the limbs, and have connected to them rods to
which are attached brass blocks E E'; the armatures F F are also attached to
springs G G which tend to draw them and the blocks E E¹ into the position
shewn on the drawing, in which the blocks prevent the armatures D D¹ from

page_text: moving towards the electro-magnets. Thus when the electro-magnet C is in circuit,
it attracts the armature F and thereby causes this to move the block E from under
the armature D, allowing this to be attracted, and thereby bringing the brushes B_B
in contact. At the same time, the electro-magnet CI being out of circuit, the
armature F¹ will be withdrawn by the spring G³, causing the block E¹ to assume
the position shown, in which it prevents the armature D₁ from moving down so as
to alter the position of the brushes.
As soon as the shunt circuit of the dynamo is broken, the armature D being
released, it rises and the block E is drawn underneath it by the spring G, thus
preventing it from operating again until the circuit is closed in the same manner
again.
The same action takes place when the electro magnet C¹ is put in circuit. When
no current is passing through the electro magnets, the armatures D D F F¹ and
blocks G G assume the position shewn, in which both sets of brushes are free from
the commutators, and are locked in that position by the blocks G G', until one or
other electro-magnet is put in action again.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In combination with two sets of commutator brushes of a dynamo machine
the use of two electro magnets having armatures connected to the brush frames, and
locking devices for preventing the motion of the armatures, and so arranged that
when the one or the other electro magnet is brought into action by the current so as to
attract its armature, this is thereby made to bring the one set of brushes in contact
with the commutator, while at the same time the locking device of the other electro
magnet prevents its armature from actuating the brush frame, substantially as
herein described.
2. In combination with two sets of commutator brushes B B B¹ B₁ of a dynamo
machine, the use of two electro magnets C C₁ having armatures D D¹ that are con-
nected to opposite sides of the pivotted brush frames, so that according as the one
electro magnet or the other is actuated by the current, the corresponding armature
brings the one or the other set of brushes in contact with the commutator, the
electro magnets CC being also provided with other armatures F F¹ connected to
locking blocks E E¹ and acted upon by springs G G¹, and so arranged that when
the electro-magnets are not excited, the locking blocks are held in such a position as
to lock the arinatures D D¹, substantially as herein described with reference to the
drawings.
Dated this 7th day of March 1889
ABEL & IMRAY,
Agents for the Applicant.