Improvements in or connected with Electric Transformers or Induction Apparatus.
Year: 1891

page_text: Date of Application, 17th Oct., 1891
Complete Specification Left, 18th July, 1892-Accepted, 20th Aug., 1892
PROVISIONAL SPECIFICATION.
Improvements in or connected with Electric Transformers or
Induction Apparatus.
We, LAZARUS PYKE and EDWARD STEPHEN HARRIS, Electrical Engineers,
of 34, New Tothill Street, in the City of Westminster, do hereby declare the nature
of this invention to be as follows:
Our invention relates to high tension transformers with liquid insulation, and
more especially to the transformers described in the Specification of Pyke &
Barnett's Patent No. 3900 of 1890, where special means are provided to promote
the circulation and cooling of the liquid used for insulation.
The objects of the improvements are, to avoid a separate cooling vessel, and
generally to simplify the construction and render the apparatus more couvenient
for use.
Instead of placing the coils in a glass vessel or container filled with insulating
liquid, and the main body of the said liquid in a separate metallic cooling vessel,
we employ a corrugated vessel having at least twice the height of the coils, and
place the coils or transformer proper at the bottom of the said vessel, so as to leave
at the top a space for the cooling liquid at least equal to the height of the coils,
the cooler being thus situated immediately above the transformer.
We prefer to make the container and cooling vessel of earthenware, either
corrugated or provided with external ribs or gills, the top and bottom being circular
and extending beyond the corrugations.
.
The said vessel or pot is open at the top and provided with a hermetically closing
lid secured to the bottom by means of a screw bolt passing axially through the
interior of the vessel. The packing between the pot and the lid is preferably
formed of a circular ring of indiarubber resting in the grooved upper edge of the
pot and provided with a lap-joint.
The said central bolt, which passes through the lid and carries at the top a screw
nut, is connected with the pot by means of a wooden base plate placed upon the
bottom of the earthenware pot and secured thereto from the inside by means of
screws passing into holes tapped into the container.
The central bolt mentioned above passes through the centre of the said wooden
base plate and is provided at the lower end with a head sunk into the said base
plate, which thus serves to distribute the strain over the surface or circumference
of the bottom of the pot.
The lid of the pot has two conical holes which are closed with plugs of india-
rubber. Through one of these plugs pass the primary wires of the transformer, and
through the other the secondary wires.
The clear height of the vessel is preferably about three times that of the coils or
transformer proper, and the radial depth of the corrugations, that is the difference
between the largest and smallest radius of the pot, is preferably about a quarter of
its radius.
The transformer proper consists preferably of concentric coils of wire arranged so
as to form a ring or hollow cylinder which may be arranged in sections or groups
separated from each other by unsized paper or other porous insulating material
which can be easily penetrated by the insulating liquid. The coils are held
together by the iron of the transformer, which is arranged in segments, hoops,
saddle pieces, or horse-shoe shaped plates placed vertically and radially, so that
each set of plates or hoops enters one of the corrugations of the vessel. Each saddle-
piece or horse shoe plate encloses on three sides a radial section of the coil; each
set of plates or saddle-pieces is applied to the coil alternately from the top and from
the bottom, and secured by corner bolts or other suitable means.

page_text: The insulating material may be of a more or less viscous nature, such as heavy
petroleum free from all volatile distillates. Great care must be taken in insulating
the secondary from the primary coils, and all materials must be thoroughly dried.
For this purpose, bags containing powdered potassium or sodium or other desiccating
substance may be placed in the axis of the coil, that is in the open space left in the
interior of the annular transformer.
Dated this 17th day of October 1891.
FAIRFAX & WETTER,
433, Strand, London, Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in or connected with Electric Transformers or
Induction Apparatus.
We, LAZARUS PYKE and EDWARD STEPHEN HARRIS, Electrical Engineers,
of 34, New Tothill Street, in the City of Westminster, 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 :-
Our invention relates to high tension transformers with liquid insulation, and
more especially to the transformers described in the Specification of Pyke &
Barnett's Patent No. 3900 of 1890, where special means are provided, to promote
the circulation and cooling of the liquid used for insulation.
The objects of the improvements are, to avoid a separate cooling vessel, and
generally to simplify the construction and render the apparatus more convenient
for use.
Instead of placing the coils in a glass vessel or container filled with insulating
liquid, and the main body of the said liquid in a separate metallic cooling vessel,
we employ a corrugated vessel having at least twice the height of the coils, and
place the coils or transformer proper at the bottom of the said vessel, so as to
leave at the top a space for the cooling liquid at least equal to the height of the
coils, the cooler being thus situated immediately above the transformer.
We prefer to make the container and cooling vessel of earthenware, either
corrugated or provided with external ribs or gills, the top and bottom being circular
and extending beyond the corrugations.
The said vessel or pot is open at the top and provided with a hermetically closing
lid secured to the bottom by means of a screw bolt passing axially through the
interior of the vessel. The packing between the pot and the lid is preferably
formed of a circular ring of indiarubber resting in the grooved upper edge of the
pot and provided with a lap-joint.
In further describing the invention, reference will be made to the accompanying
drawings, of which
Fig. 1 is a vertical section and Fig. 2 half horizontal section and half plan of
a transformer embodying our improvements.
A is the primary coil.
B. the secondary coil.
C, C¹ the iron of the transformer.
Dan earthenware pot serving as cooling vessel, and provided with an axial tube d
reaching up to the top of the vessel.
d are lugs formed on the bottom of the vessel D and serving to support the
transformer.
E is the lid.
e are india rubber packing rings placed in circular grooves between the vessel and
the lid.
F is the central bolt for holding down the lid.
G, G, are bridge pieces or washers connecting the bolt with the vessel and lid.
M is a wooden ring placed on the top of the transformer.

page_text: N are wooden distance pieces or stays fixed to the ring M and extending up to
the lid E.
The lid of the pot has two conical holes (not shown) which are closed with plugs
of indiarubber. Through one of these plugs pass the primary wires of the trans-
former, and through the other the secondary wires.
The transformer proper consists preferably of concentric coils of wire arranged
so as to form a ring or hollow cylinder which may be arranged in sections or
groups separated from each other by unsized paper or other porous insulating
material which can be easily penetrated by the insulating liquid. The coils are
held together by the iron of the transformer, which is arranged in segments, hoops,
saddle pieces or horse-shoe shaped plates C, C¹ placed vertically and radially, so
that each set of plates or hoops enters one of the corrugations of the vessel. The
plates or saddle pieces of each set are applied to the coil alternately from the top (C)
and from the bottom (C').
The insulating material may be of a more or less viscous nature, such as heavy
petroleum free from all volatile distillates. Great care must be taken in insulating
the secondary from the primary coils, and all materials must be thoroughly dried.
For this purpose, bags containing powdered potassium or sodium or other desiccating
substance may be placed in any convenient part of the vessel.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The combination of a transformer, with a closed container and cooling vessel
which contains in its lower part the said transformer and above the same an oil
space at least equal to the height of the coils, substantially as described.
2. The combination of an annular transformer consisting of concentric coils of
wire and saddle shaped plates of iron applied alternately from the top and from the
bottom, with a corrugated oil vessel which contains the transformer and insulating
liquid and in which each corrugation holds a set of the said saddle plates, substan-
tially as described.
Dated this 16th day of July 1892.
FAIRFAX & WETTER,
433, Strand, London, Agents.