Improvements in Apparatus for Automatically Controlling and Regulating Dynamo-electric Machines and Motors.
Year: 1890

page_text: Date of Application, 17th Apr., 1890
Complete Specification Left, 7th Jan., 1891-Accepted, 14th Feb., 1891
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Automatically Controlling and
Regulating Dynamo-electric Machines and Motors.
I, JAMES RADCLIFFE, of East Retford, in the County of Nottingham,
Telegraph Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention consists, firstly, in automatically changing or altering the angular
position of the segments of the commutator, with regard to the windings of the
armature, in such a manner as to enable the machine to be run in either direction
without shifting the brushes.
Secondly, in automatically adjusting the lead to suit all speeds and preventing
sparking.
Thirdly, in a particular arrangement in combination with the above for cutting a
resistance into any part of the circuit for regulating the strength of the current or
the difference of potential between any two points.
In order to accomplish these ends I affix or attach the commutator to the hub of
the driving pulley, the said hub being free to move within certain limits in a
circular direction on a second hub or sleeve, the latter being also free to move
within certain limits on the armature shaft, the amount of motion in each case
being limited by means of projections or pins in the armature shaft and second hub
engaging in segmental notches or slots in the second and first hubs respectively.
Between the outer or pulley hub and the inner or second hub I mount or affix a
pair of differential springs arranged so as to be equally balanced when the
projection or pin on the inner hub is in the centre of the segmental slot in the
outer hub.
I sometimes employ in place of the segmental slots, helical or diagonal slots as
described in my Patent Specification No. 12928, of October Eleventh 1886, or I
may employ a screw thread in one or both of the hubs so as to produce longitudinal
motion, such motion being applicable to various purposes but particularly to the
purpose of regulating the current or cutting the dynamo in or out of circuit.
I also employ in combination with the above, one or more automatic electric
switches as described in my Specification No. 5878 of April Thirtieth 1886 for
controlling the current passing between the generator and accumulators.
Dated this 17th day of April 1890.
JAMES RADCLIFFE.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Automatically Controlling and
Regulating Dynamo-electric Machines and Motors.
I, JAMES RADCLIFFE, of East Retford, in the County of Nottingham,
Telegraph 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:—
This invention consists (1st) In automatically changing or altering the angular
position of the segments of the commutator with regard to the windings on the
armature in such a manner as to enable the machine to be run in either direction
without-shifting the brushes.
(2nd) In a narticular method of adiusting the lead.

page_text: (3rd) In a particular arrangement in combination with the above for automatically
cutting a resistance into any part of the circuit or circuits for regulating the
strength of the current or the difference of potential between any two points.
In order to accomplish these ends I employ the arrangements set forth as follows,
with reference to the accompanying drawings,
Where D, Fig. 1, is the dynamo, A a section of the commutator attached by
means of the sleeve and flange 'B to the hub of the driving pulley P, which is free
to move on the inner hub H.
To the opposite face of the web of the pulley I attach a cylindrical box C, on
the inner surface of which are segmental projections E. E', Fig. 2, through which
pass the adjusting screws S. S¹.
The inner hub H, Figs. 1 and 2, which in this case is fixed to 'the dynamo
shaft I, carries segmental projections G. G, which engage alternately with S. 'S',
according to the direction in which the pulley P is driven.
The segments of the commutator A, are connected with the coils of the
armature K, by means of insulated flexible connections F, thus allowing the
pulley P, and commutator A, to turn on the hub H, through an arc determined
by the position of the screws S. S', the said screws being adjusted so as to give the
requisite lead to the commutator in either direction.
In order to effect regulation as the speed increases I may sometimes arrange the
hub H', Figs. 3 and 4, so as to be moveable in a circular direction on the dynamo
shaft I', such movement being limited by means of a pin L, in the shaft 1' engaging
in a segmental slot in the hub H', or by means of segmental projections and adjusting
screws as shewn in Fig. 2.
The commutator A, Fig. 3, in this instance being fixed to the hub H, which
also carries a pin N, which engages in the right and left handed helical slot M, in
the hub of the pulley so that, on the pin N, riding to either end of the helical
slot M, longitudinal motion will be imparted to the pulley P', which motion being
transmitted, by means of the pin W attached to the loose ring V to the lever T,
may be used to actuate a switch or other mechanism for cutting a resistance, or
accumulators into any part of the circuit or circuits. For the purpose of
maintaining the pin N, normally in the centre of the slot M, I employ a pair
of differential or antagonistic springs X, X', which may be of any -suitable form,
one end of each being fixed to the pulley and the other end to the hub H', such
springs being so adjusted as to maintain the pin in the centre of the slot M, until a
certain predetermined strain is put upon the armature owing to increase of speed
which being attained the tension of the springs X. X' will be overcome and the
pin N, riding along the slot M, will actuate the lever T and any mechanism
attached thereto and so effect the desired adjustment above described.
In connection with the above I may employ any known form of brush and brush-
holder but preferably that shewn in Figs. 1 and 5, in which 0, 0, 0, 0, are upright
levers jointed at the bottom as shewn and carrying at their upper extremity the
brushes Q, which may be of any suitable material, copper gauze for instance, and
set radially as shewn, with respect to the commutator A, the necessary pressure
between the brushes and commutator being maintained by means of the insulated
spiral springs R.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the saine is to be performed, I declare that what I
claim is:
1. Automatically changing or altering the relative angular positions of the
segments of the commutator and armature of a dynamo electric machine for the
purpose of enabling such machine to be run in either direction without altering
the position of the brushes.
2. The particular method or methods of changing or altering the relative
angular positions of the segments of the commutator and armature of a dynamo
electric machine or motor above described with reference to the drawing.

page_text: 3. The employment of a double helical slot in the hub of the driving pulley of a
dynamo electric machine or motor in the manner and for the purpose above
described.
Dated this 17th dox of December 1800
JAMES RADCLIFFE.