Improvements in Secondary Generators, Transformers, or Converters of Electricity.
Year: 1889

page_text: Date of Application, 16th Nov., 1889
Complete Specification Left, 15th Apr., 1890-Accepted, 17th May, 1890
PROVISIONAL SPECIFICATION.
Improvements in Secondary Generators, Transformers, or Converters
of Electricity.
We JOHN DIXON GIBBS Esquire and EMILE FESQUET Engineer both of 18 Warwick
Street Regent Street in the County of Middlesex do hereby declare the nature of
this Invention to be as follows
This Invention relates to the electrical induction apparatus called secondary
generators transformers or converters wherein two coils (the secondary and primary)
of insulated conducting strips wires or cables are placed in juxtaposition and are
surrounded by soft iron plates forming a magnetic field. Our Invention relates to
this magnetic field and has for its object to provide a convenient arrangement
presenting magnetic circuits of very short length of its component members around
the primary and secondary conductors.
According to this Invention we make the magnetic field up of soft iron plates of
F shape which we place alternately in opposite positions in pairs so that they between
them form two spaces in which the primary and secondary conductors are situated,
the longitudinal sides of each pair of the F pieces extending one along one side of
the coils and the other along the other side of the coils the end transverse members
of each pair of the F pieces extending across the remaining sides of the coils and
the mid-members of each pair of the F pieces occupying the space between the coils
at the centre. Another pair of these F pieces is placed in metallic contact with the
first pair so that it covers the spaces or joints between the other pair. These double
pairs are placed on each other in any desired number and are insulated from each
other by paper or other insulating material. Thus each double pair forms a
magnetically closed circuit of very small length.
The required number of plates having been put in place around the coils the whole
are kept in place by any suitable means such for instance as two cast iron frames
bolted together.
COMPLETE
SPECIFICATION.
Improvements in Secondary Generators, Transformers, or Converters
of Electricity.
We JOHN DIXON GIBBS Esquire and EMILE FESQUET Engineer both of 18 Warwick
Street Regent Street in the County of Middlesex 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 the electrical induction apparatus called secondary
generators transformers or converters wherein two coils (the secondary and primary)
of insulated conducting strips wires or cables are placed in juxtaposition and are
surrounded by soft iron plates forming a magnetic field and the said Invention relates
to this magnetic field and has for its object to provide a convenient arrangement
presenting magnetic circuits of very short length of its component members around
the primary and secondary conductors.
According to this Invention the magnetic field is composed of soft iron plates of
F shape which we place alternately in opposite positions in pairs so that they between

page_text: them form two spaces in which the primary and secondary conductors are situated
the longitudinal sides of each pair of the F pieces extending one along one side of the
coils and the other along the other side of the coils the end transverse members of
each pair of the F pieces extending across the remaining sides of the coils and the
mid-members of each pair of the F pieces occupying the space between the coils at
the centre. Another pair of these F pieces is placed in metallic contact with the first
pair so that it covers the spaces or joints between the other pair. These, double pairs
are placed on each other in any desired number and are insulated from each other by
paper or other insulating material. Thus each double pair forms, a magnetically
closed circuit of very small length.
The required number of plates having been put in place around the coils the whole
are kept in place by any suitable means such for instance as two cast iron frames
bolted together.
The accompanying drawings shew arrangements according to this Invention.
ansverse section.
Figure 4 is a modification of the arrangement of the coils.
Figure 5 shews two of the F shaped plates placed together to form the first pair
of a double pair and
Figure 6 shews two of the F shaped plates placed together to form the other pair
of the said double pair.
The apparatus consists of these plates f forming an iron core the primary circuit P
and the secondary circuit s. The primary circuit is formed of an insulated conducting
strip wire or cable of a suitable length which may be wound on the lathe on a
flat shaped mandrel with its ends rounded or oval. The secondary circuit is formed
of an insulated conducting strip wire or cable of a suitable diameter which may be
wound in the same way. The two coils are placed side by side as shewn in Figure 3.
or one over the other as shown in Figure 4. In all cases the primary and secondary
coils are separated from each other and from the surrounding iron plates by insulating
material d.
The iron core is formed of thin soft iron F shaped plates f forming when placed
together in double pairs as described a magnetic field of very short length around
the primary & secondary conductors. Two of these plates are placed together as
shewn in Figure 5 and then two others are placed together as shewn in Figure 6.
These two pairs of plates are placed in metallic contact with each other in such a way
as to "break bond" that is to say so that the gaps or meeting edges of either pair are
covered by the continuous portions of the other pair. These double pairs are placed
on each other in any desired number to form the magnetic field & the said double
pairs are insulated from the adjacent double pair or double pairs by paper or other
insulating material. Thus each double pair forms a magnetically closed field of very
short length around the two coils.
The required number of plates f having been put in position. they are.kept in
place preferably by two cast iron frames g bolted together by the bolts h as shewn
in Figures 1 and 2.
We do not limit ourselves to the precise form of the plates as shewn provided.
they are substantially F shaped for instance the plates may be shaped as in Figure 7
and in either case the outer corners may be cut off as indicated in, dotted lines in
the said Figure.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed we declare what we
claim is :-
First In or for secondary generators transformers or converters of electricity

page_text: iron plates shaped and disposed as hereinbefore described so that they form a closed
magnetic field of very short length round the primary and secondary coils.
Second: A secondary generator transformer or converter of electricity made of
the combination of parts hereinbefore described and shewn in Figures 1 to 4 of
the accompanying drawings.