IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES
Year: 1885

page_text: GEORGE TOLMAN Electrical Engineer 37 Pearson St. Wolverhampton HENRY
DENTON, Agricultural Engineer St. Marks St. Wolverhampton do hereby declare
the nature of our invention for IMPROVEMENTS IN DYNAMO ELECTRIC MACHINES
to be as follows:-
Relates to the field magnets, armatures, brush holders, & in the winding of the
magnets & armatures.
The field magnet is constructed as follows, a square or rectangular, iron base
plate with holding down feet, having a pole piece along the centre with an iron
arm or support for the iron bearings at the end of pole piece, screwed on this base
plate are two electro magnets, square or rectangular in shape, placed parallel to the
pole pieces, on the top of the said magnets is placed (& screwed down) an iron plate
having a pole piece also parallel with & between the magnets, attached to this pole
piece & plate is an iron arm for supporting the iron bearings. This magnet forms
a square or rectangular shape, the two electro magnets each has a neutral pole
piece along the centre of both sides of the magnets & is parallel with the armature.
The magnets may have four active poles, & may be arranged as a compound series
of magnets..
Two or any number of polár faces may be attached to the magnets. The entire
magnet, base plate, pole pieces & arins may be constructed of wrought & cast iron
combined, or seperately.
The insulated wire is wound on the magnets parallel to the wire on the armature
in any ordinary well known way.
When wound for what is known as compound winding, two of the coils are
wound with fine wire & connected to the brushes, the thick or series wire is wound
on the other two coils..
The armature is constructed as follows according to this invention We make a
frame of metal of non-magnetic or magnetic material (or of any insulator such as
vulcanized fibre) composed of a bush or nave around which & parallel to the
spindle, is a number of arins the length of the armature, these arms are slotted
& perforated for the purpose of cooling the armature, by casting a slot in, or the
arms nay. be made half the thickness & a loose perforated side may be fitted to it,

page_text: The perhiphery of the arms are then turned true & a.thread cut on each end, the
iron core of armature is composed of a number of sheet iron rings with pieces cut
out to slide along the arms, these sheet iron rings are kept slightly apart by
means of distant pieces of insulating material, by this means there is a slight air
space between the rings.
$
Two rings of insulating material is then screwed on the ends of the arms this
gives a laterall pressure to all the sheet iron rings & makes them fit as close as the
distant pieces will allow, when this armature is revolving the air enters by the
perforations & slotted arms throughout the seperated rings & out of the other
arms which is arranged for this purpose. The armature is turned up true & fits
very close to the pole pieces (the winding may be performed in the ordinary
manner as Gramme' rings are wound, with round strand, ribbon, or square wire.in
any number of layers, but preferably with one layer of square or ribbon wire, same
as in Grammes plating machines, this winding being common we do not claim it).
Our improved method of winding the armature according to this invention is
carried out as follows, the ring armature is preferably divided into an odd number
of sections for example eleven,' supposing the winding commences at No. 1-two
sections are then wound & a loop is taken off, every two sections is then wound &
a loop taken off, right round the armature, continue the winding past No. 1-a loop
is then taken out between No. 1-& No. 2 section & the winding is continued, & a
loop is taken out between every two sections till No. 1 is arrived at again then
this is joined to the end of the wire, the ring will then have two windings, but
not independent of each other, a current entering at any point, will make two
circuits round the armature.
The brush holder constructed according to this invention consists in having the
hole tapped or screwed right through, with a clamping device for locking when
brush is adjusted, & making good electrical contact.
The bush pin is screwed to screw in the tapped hole in brush holder this saves
having collers on each side of brush, & by merely turning the pin round, the
brush is moved laterally on any portion of the collector which is not worn down.
The quadrant for holding the brush pins has a similar clamping device to the
brush holder.
The collector strips according to this invention, are made of unannealed malleable
iron, being in this state very hard, they cannot be turned, but will have to be
mounted & trued by an emery wheel, or ground in any similar manner, by reason
of this hardness, they will wear much longer than any other material.

page_text: Improvements in Dynamo Electric Machines.
GEORGE TOLMAN Electrical Engineer 37 Pearson St. Wolverhampton HENRY
DENTON Agricultural Engineer, St. Marks St., Wolverhampton, we do hereby
declare the nature of our invention for IMPROVEMENTS IN DYNAMO ELECTRIC
MACHINES and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
Our Invention relates to the field magnets armature, brush holders, & in the
winding of the magnets & armatures.
The field magnet according to this invention is constructed as follows a square
or rectangular base plate with holding down feet Fig. 5, having a pole piece along
the centre with an iron arm B Fig. 4, or support for the iron bearings at the end
of the pole piece, These bearings may also be of non-magnetic material screwed
on this base plate are two electro magnets square or rectangular in shape, placed
parallel to the pole pieces, on the top of the said magnets is placed & screwed
down an iron plate having a pole piece also parallel with & between the magnets,
attached to this pole piece & plate is an iron arm A Fig. 4 for supporting the
iron bearings, This magnet forms a square or rectangular shape, the two electro
magnets each has a neutral pole piece NP NP¹ Fig. 1 along the centre of both
sides of the magnets & is parallel with the armature These neutral pole pieces has
for its object the placing of the neutral line of magnet more central & close to the
armature. The magnets may have four active poles N N' S S¹ Fig. 2 & may be
arranged as a compound series of magnets Fig. 3 Two or any number of polar
faces PF PF PF Fig. 1, 23 may be attached to the magnets, These polar
faces has for its object the utilization of the external magnetism, The entire
magnet base plate pole pieces & arms may be constructed of wrought & cast iron
combined, or seperately.
The insulated wire is wound on the magnets parallel to the wire on the
armature in any well known way.
When wound for what is known as compound winding, (Fig. 1 shows the
magnet with its four coils) two of the coils are wound with fine wire & connected
to the brushes, The thick or series wire is wound on the other two coils and
connected in the ordinary manner for self regulating.
The armature is constructed as follows according to this invention, We make a
frame of metal of non-magnetic or magnetic material (or of any insulator such as
vulcanized fibre), composed of a bush or nave around which & parallel to the
spindle is a number of arms the length of the armature shewn at Fig. 4, 6, & 7
these arms are slotted & perforated at C Fig. 4 also at 6 & 7 for the
purpose of

page_text: cooling the armature, by casting a slot in the arms, or the arms may be made half
the thickness & a loose perforated side may be fitted to it Fig. 6 & 7.
The perhiphery of the arms are then turned true & a thread cut on each
end D D¹ Fig. 4 the iron core of armature is composed of a number of sheet iron
rings A Fig. 6, B Fig. 7 with pieces cut out to slide along the arms, these sheet
iron rings are kept slightly apart by means of distant pieces of insulating
material B Fig. 6, by this means there is a slight air space between the rings.
•
Two rings of iron or insulating material E E¹ Fig. 4 is then screwed on the
ends of the arms, this gives a lateral pressure to all the sheet iron rings & makes
them fit as close as the distant pieces B Fig. 6 will allow, when this armature is 1
revolving the air enters by the perforated & slotted arms Fig. 6; A Fig. 7 through-
out the seperated rings & out of the other arms which is arranged for this purpose.
The armature is turned up true & fits very close to the pole piece.
The winding may performed in the ordinary manner as Gramme rings are
wound in any number of layers but preferably with one layer of square or ribbon ]
wire, same as in Gramme's Plating Machines.
Our improved method of winding the armatures according to this invention is
carried out as follows, the urmature is preferably divided into an odd number of
sections for example eleven supposing the winding commences at No. 1 two
sections (from No. 1-past 7 to 2) are then wound & a loop or joint is taken off
at 2 (Fig. 8) continuing the winding from 2 to 3, 3 to 4, 4 to 5, 5 to 6, Fig. 8,
taking or forming a loop or joint at each of these figures.
Continue the winding from No. past No. 1 to No. 7, then to No. 8, 9, 10, 11
& to No. 1, then join these ends together The loops are joined in succession to
the commutator strips in the ordinary well known manner. The armature will
then have two windings, but not independent of each other, a current entering at
any point will make two circuits round the armature increasing both electro
motive force & current, when generating.
The brush holders constructed according to this invention consists in having the
hole tapped or screwed right through B Fig. 10 with a clamping device for locking
when brush is adjusted C Fig. 10 & making good electrical contact.
The brush pin is screwed B Fig. 9 to screw in the tapped hole in the brush
holder B Fig. 10 this saves having collers on each side of brush holder, & by
merely turning the pin Fig. 9 round, the brush holder travels laterally on any
portion of the collector required.
The quadrant fig. 15 & 16 has a similar clamping device to the brush holder.
The collector strips according to this invention are made of unannealed malleable
iron (in any well known form) being in this condition hard they will wear much
longer than any other metal.
The provisional drawings are those referred to in the complete specification.
Having now particularly described and ascertained the nature of the said
invention & in what manner the same is to be performed, we declare what we
claim is
(1) In a field magnet constructed of a square or rectangular form having two
active and two neutral poles, in a modification having four active poles, in a series
of magnets, in having iron arms A B Fig. 4 in combination with iron bushes or
bearings, in the employment of polar faces FP1 FP" FP Fig. 1 2 3 substantially
as & for the purpose herein described & shewn by the figures 1 2 3 4 & 5 of the
accompanying drawings.
(2) In an armature constructed of a frame having a number of perforated arms
mounted with iron rings with an air space between each ring, screwed up laterally
with washers of insulating material.
In the winding of armatures substantially as and for the purpose herein.
described & shewn by figures 4, 6, 7, & 8 of the accompanying drawings.
4

page_text: (3) In a brush holder the hol B Fig. 10 tapped to screw on a pin, in combination
with the locking device & lateral adjustment substantially as & for the purpose
herein described & shewn by figures 9 10 11 & 12 of the accompanying drawings.
(4) In a collector, the strips formed of unannealed malleable iron substantially
as & for the purpose herein described.
GEORGE TOLMAN.
HENRY DENTON.