Improvements in Dynamo Electric or Electro Dynamic Machines.
Year: 1895

page_text: Date of Application, 23rd Aug., 1895
Complete Specification Left 21st May 1806 Accented
27th lung 1806
PROVISIONAL SPECIFICATION.
Improvements in Dynamo Electric or Electro Dynamic Machines.
I, JOHN GRICE STATTER, of 68 Victoria Street Westminster, in the County of
Middlesex, Electrical Engineer, do hereby declare the nature of this invention to
be as follows:-
My invention relates to improvements in dynamo electric or electro dynamic
machines of the two pole type.
My object is to provide an improved means of attaching the field magnets to the
yoke and bedplate, so that they may be readily removed for examination or
repair, and to provide also improved means of ventilating the armature core and
windings.
I confine that part of my invention which relates to the means of fixing the
field magnets to machines of the inverted vertical two pole type such for example
as that shewn in Fig. 1 or to machines similar to that shewn in Fig. 1, so far as the
bed plate is concerned, but with or without a second pair of magnet limbs and coils
above the armature. In such machine it is now customary to provide the yoke of
the magnets-if there are two limbs and two coils only, forming a single circuit
field magnet-as an integral part of the bed plate casting. And if there are two
limbs of the magnets above the armature as well as two below, it is still customary
to provide the yoke for the lower pair of magnets as above described.
And where magnet limbs of different material to that employed for the bedplate
are used these are attached to the bedplate (with its yoke piece cast in one) by
means of screws or bolts.
To such machines my improved means of fixing the field magnets is applicable.
Figure 1 shews a side and an end elevation of a dynamo or motor constructed
in accordance with my invention.
In the machine illustrated each limb, of the field magnets of a single circuit
inverted vertical machine of the two pole type M, is constructed of a number of
rectangular bars of wrought iron fastened together permanently by means of bolts
or rivets passing through all of them.
Each limb of the field magnets M has a half dove tail groove planed along one
side, and this fits with a correspondingly shaped tongue planed out of that part of
the yoke which projects above the surface of the bed plate, and the magnet is
forced home by means of the dogs or clamps K, K, of which there are two in the
machine shewn.
Each of the dogs shewn at K, K₁, is provided with two conical projections, one
at either end and each projection fits into a parallel hole, one such hole being
drilled in the magnet limb and the other one in the bed plate. The operation of
this joint needs no further explanation, and it will be seen that by taking out the
bolts L, L, the magnet is free to be removed.
Figures 2, 3, & 4, shew equivalent forms of joint and it will be seen that in
Fig. 4 the bolt L, may be dispensed with, and also that any of the forms of clamp
may be employed no matter whether the joint on the inner side of the magnet be
dovetailed, shaped, or dowelled.
1 may also employ dowels with the dovetail or the L joint. And I do not
confine myself to the specific forms of joint. shewn there being other mechanical
equivalents which would carry out the general principle of the invention.
The remaining portions of the field magnets and bearings of my improved
dynamo are not novel and will not be described.
1

page_text: The armature is novel and of the ring form but has a smaller internal space than
is usual with such armatures. This space I utilize either for ventilating purposes
only, in the manner hereinafter described, in which case the whole of the conductors
are laid on in drum fashion; or it may contain the inner portion of an additional
Gramme winding as well as providing space for ventilation.
Figure 5 is a side elevation of an armature constructed according to my invention
and is shewn partly in section, the winding has been omitted for the sake of
clearness.
The stampings forming the core are-shewn in Figure 6, they are blanks of thin
wrought iron shaped as shewn at S.
N represents the spindle and is provided with featherways corresponding in
number, position, & width to the interval projections of the stampings forming the
core.
The stampings are supported by two end plates usually made in cast steel &
these are shaped as shewn in Figures 5, 7, & 8, at P & P₁.
The manner in which these end plates are shaped and applied is an important
factor in my improved armature, since by making use of long buttress shaped pieces
to connect the end plate proper, (which is here a flat ring) and its hub, (which is
a strong ring on the spindle, backed at the ends by either collars or nuts) I am
enabled to maintain the full air space between the inner part of the armature, and
the spindle or the hub of end plate.
The direction of this channel is curved upwards but since it is needed for the
accommodation of either wires and an air current, or for an air current only the
change of direction when made by shaping the boss to a curve is not a
disadvantage.
In Figure 5 a set of fan blades are represented at T, secured to the end cover,
which is by the fan split up into two parts V & W. I sometimes only provide
eyelets in the end cover and sometimes fan blades attached to the back of the
commutator.
When Gramme windings are employed upon my improved armature they are
never employed alone but always in combination with a drum winding (Sturgeon,
or Siemens, or the like) as described in my Application No. 6528 of 1893.
The Gramme convolutions being coupled up either as reverser turns or as an
auxiliary winding in series or in parallel with a drum, and with or without a
separate commutator; or as the primary or the secondary of a continuous current
transformer.
When such Gramme convolutions are employed say as reverser turns or otherwise,
as herein before described, I usually prefer to embed them in slots in the outer
periphery or in holes near to that periphery and so leave a clear surface for the
principal winding laid on in drum fashion as herein before described. A proper
layer of insulating material being placed over the whole armature after the
Gramme winding has been completed.
Dated this 22nd day of August 1895
COMPLETE SPECIFICATION.
Improvements in Dynamo Electric or Electro Dynamic Machines.
I, JOHN GRICE STATTER, of 68 Victoria Street, Westminster, in the County
of Middlesex, 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 :-
My invention relates to improvements in dynamo electric or electro dynamic
machines of the two pole type.

page_text: My object is to provide an improved meaus of attaching the field magnets to
the yoke and bed-plate, so that they may be readily removed for examination or
repair and to provide also improved means of ventilating the armature core and
windings.
I confine that part of my invention which relates to the means of fixing the-
field magnets to machines of the inverted vertical two pole type such for example
as that shewn in Fig. 1, in the drawings filed with my Provisional Specification,.
or to machines similar to that shewn in Fig. 1 so far as the bed plate is concerned
but with or without a second pair of magnet limbs and coils above the armature..
In such machines it is now customary to provide the yoke of the magnets-if there
are two limbs and two coils only, forming a single circuit field magnet-as an
integral part of the bed-plate casting. And if there are two limbs of the magnet
above the armature as well as two below it is still customary to provide the yoke
for the lower pair of magnets as above described.
And where magnet limbs of different material to that employed for the bed-plate
are used these are attached to the bed-plate (with its yoke piece cast in one) by
means of screws or bolts.
To such machines my improved means of fixing the field magnets is applicable.
Fig. 1, in my drawings filed with my Provisional Specification shews a side and
an end elevation of a dynamo or motor constructed in accordance with my
invention.
In the machine illustrated each limb of the field magnet of a single circuit-
inverted vertical machine of the two pole type M is constructed of a number of
rectangular bars of wrought iron fastened together permanently by means of bolts
or rivets passing through all of them.
Each limb of the field magnet M has a half dove-tail groove planed along one
side and this fits with a correspondingly shaped tongue planed out of that
part of the yoke which projects above the surface of the bed plate and the magnet
is forced home by means of the dogs or clamps K, K, of which there are two in
the machine shewn.
Each of the dogs shewn at K, K, is provided with two conical projections one.
at either end and each projection fits into a hole drilled parallel but altered some-
what in shape by the act of forcing the conical projection on the dog; one such
hole being drilled in the magnet limb and the other one in the bed plate. The
operation of this joint needs no further explanation and it will be seen that by
taking out the bolts L, L, the magnet is free to be removed.
It is not necessary that the magnet limb should be made up of a number of bars
as herein before described. It may be formed out of one piece..
Figs. 2, 3 & 4 shew equivalent forms of joint and it will be seen that in Fig. 4.
the bolt L, may be dispensed with, and also that any of the forms of clamp may be
employed no matter whether the joint on the inner side of the magnet be dove-.
tailed, shaped or dowelled.
I may also employ dowels with the dovetail or the L joint. And I do not
confine myself to the specific forms of joint shewn there being other mechanical
equivalents which would carry out the general principle of the invention. As
for example using a perfectly plane surface parallel to the axis of the magnet
limb as a joint surface with the yoke piece on the bedplate where strong dowels are
used. The remaining portions of the field magnets and bearings of my improved
dynamo are not novel and will not be described.
The armature is novel and of the ring form but has a smaller internal space
than is usual with such armatures. This space I utilize either for ventilating
purposes only in the manner hereinafter described, in which case the whole of the
conductors are laid on in drum fashion, or it may contain the inner portion of an
:dditional Gramme winding as well as providing space for ventilating.
Figure 5 is a side elevation of an armature constructed according to my invention
and is shewn partly in section the winding has been omitted for the sake of
clearness.

page_text: The stampings forming, the core are shewn in Fig. 6. They are blanks of thin
wrought iron shaped as shewn at S. The length of the internal projections
depending upon the amount of internal space required either for windings or for
ventilation or both.
N represents the spindle and is provided with feather ways corresponding in
number, position, and width to the internal projections of the stampings forming
the core.
The stampings are supported by two end plates usually made in cast steel and
these are shaped as shewn in Figs. 5,7 & 8, at P and P1.
The manner in which these end plates are shaped and applied is an important.
factor in my improved armature, since by making use of long buttress shaped
pieces to connect the end-plate proper (which is here a flat ring) and its hub,
(which is a strong ring on the spindle backed at the ends by either collars or
nuts) I am enabled to maintain the full air space between the inner part of the
armature and the spindle or the hub of end, plate.
The direction of this channel is curved upwards but since it is needed for the
accomodation of either wires and an air current, or for an air current only
the change of direction when made by shaping the boss to a curve is not a
disadvantage. In Figure; 5. a set of fan. blades are represented at T secured to
the end cover which is by the fan split up into two parts V and W. 1. sometimes
only provide eyelets in the end-cover and sometimes fan blades attached to the
back of the commutator.
When Gramme windings are employed upon my improved armature they are
never employed alone but always in combination with a drum winding (Sturgeon
or Siemens or the like) as described in my Application No. 6528 of 1893.
The Gramme convolutions being coupled up either as reverser; turns or as an
auxiliary winding in series or in paralled with a drum and with or without a
separate commutator; or as the primary or the secondary of a continuous current
transformer.
When such Gramme convolutions are employed say as reverser turns or otherwise
as herein before described I usually prefer to, embed them in slots in the outer
periphery or in holes near to that periphery and so leave a clear surface for the
principal winding laid on in drum fashion as herein before described. A suitable
layer of insulating material being placed over the whole armature after the Gramme
winding has been completed.
Where the drum winding consists of bars connected at the ends by; a scroll of
copper the buttress. shaped supports for the end plates are notched to receive
and support that end of the carrier for such scroll at the end, nearest to the
armature core.
Having now particularly described and ascertained the nature of my said inven
tion and in what manner the same is to be performed I declare that what I
claim is :
1. In a dynamo electric or electro-dynamic machine the method of fixing the field
magnet limbs, to the bed-plate substantially as set forth.
2...The specific forms of joint, shewn in Figs. 1, 2, 3 and 4, of the drawings:filed
with my Provisional Specification.
3. In a dynamo. electric or electro-dynamic machine the method of supporting.
and fixing the discs forming the armature core substantially as set forth.
4.. The specific form of the supports and the core discs shewn in Figs. 5, 6, 7 and 8
of the drawings filed with my Provisional Specification.
Irated this 21st day of May: 1896.
aved this 21st day of May. 1896.
..J., G. STATTER, Assoc. Mem. Inst. C.E.,
.68 Victoria Street,, Westminster, London, S.W.