Automatic Coupling for Electromotors.
Year: 1893

page_text: Date of Application, 24th Aug.. 1893
Complete Specification Left, 4th May, 1894-Accepted, 9th June, 1894
PROVISIONAL DI POTEICATION.
[Communicated from abroad by Messrs. SIEMENS & HALSKE, of Berlin, in the
German Empire, Electrical Engineers.]
Automatic Coupling for Electromotors.
We, SIEMENS BROTHERS & Co., LIMITED, of 12 Queen Anne's Gate,.
Westminster, in the County of Middlesex, Electrical Engineers, do hereby declare:
the nature of this invention to be as follows:-
:-
This invention relates to an automatic coupling of an electromotor to the spindle.
driven by it, that is to say, a coupling which connects the motor to the spindle when
current is supplied to the motor.
For this purpose, the spindle of the armature is free to move to a certain extent
lengthwise in its bearings, and, when no current is passing it is held by a spring in
such a position that a crank on its end is out of range with a crank on the end of
the spindle to be driven by it; but, when the motor is put in circuit, the field.
magnets, which partly surround the armature, act on it like a solenoid on its core,.
drawing the armature forward in opposition to the spring, and thus the two cranks
above mentioned become engaged, the motor thereupon driving the spindle. To.
allow for the longitudinal movement of the armature spindle, the commutator is.
made of such length that the stationary brushes remain in contact with its segments.
in both of its extreme positions.
Dated this 24th day of August 1893.
ABEL & IMRAY,
Agents for the Applicants..
COMPLETE SPECIFICATION.
Automatic Coupling for Electromotors.
We, SIEMENS BROTHERS & Co., LIMITED, of 12 Queen Anne's Gate,.
Westminster in the County of Middlesex, Electrical Engineers, 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 :—
This invention relates to an automatic coupling which connects an electromotor
to the spindle or shaft driven by it when current is supplied to the motor..
When operating smaller machinery or apparatus (such as regulating apparatus,.
railway signal apparatus &c.) by means of electromotors it is frequently required,
when throwing the motor out of action, to simultaneously disconnect the same
from the shaft or spindle driven thereby in order to bring the driven apparatus at
once to a state of rest, and prevent it from being carried round by the residual
momentum of the rotating part of the motor, alter the current has been cut off.
For this purpose the following arrangement is employed, which is applicable.
more particularly in cases where a very high degree of efficiency in the motor is.
not required.
The motor armature or rotating part, together with its shaft, is free to shift
longitudinally in its bearings within certain limits, and when no current is passing
through the windings of the motor, a spring or weight acts upon the armature.
shaft so as to tend to withdraw it and the armature from the field magnets to such
an extent that the one part of a coupling fixed on the end of the armature shaft is.
n

page_text: drawn out of engagement with the second part of the coupling on the shaft or
spindle to be driven thereby, while when the motor is put in circuit the attraction
exercised by the field magnets upon the armature surrounded thereby, will cause
this and also its shaft to move back into their working position and consequently
to effect the engagement of the two parts of the coupling.
On the accompanying drawings is shewn by way of example a construction of
electromotor having an automatic coupling according to the above described
invention. Fig. 1 shews the motor when no current is passing through, the
armature A and its shaft B being partially withdrawn from the field magnets C by
a spring D, so that a crank E on the end of the armature is withdrawn from
engagement with the arm F on the driven shaft G. On the motor being put in
circuit, as at Fig. 2 the armature and shaft are drawn inwards by the field magnets
against the action of the spring, and the pin of the crank E is consequently made
to engage with the arm F.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
In an electromotor, arranging the armature and its shaft in such manner that
they are free to be shifted longitudinally by the action of a spring or weight when
no current is passing through the motor windings, whereby the one part of a clutch
on the armature shaft is drawn out of engagement with the other part of the
clutch on the shaft to be driven, while when the motor is put in circuit, the
attraction exercised by the field magnets causes the armature and its shaft to be
drawn back into their working position with the clutch engaged, substantially as
described.
ABEL & IMRAY,
Agents for the Applicants.