Improved Manufacture of Magnet Cores with Ventilating Passages for Transformers and the like.
Year: 1899

page_text: Date of Application, 15th Nov., 1899-Accepted, 23rd Dec., 1899
Improved Manufacture of Magnet Cores with Ventilating Passages
for Transformers and the like.
I, OTTO TITUS BLÁTHY, of II Grosse Rochusgasse, Budapest, Hungary,
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:-
Various arrangements have heretofore been proposed for effecting the ventila-
tion of the sheet iron cores of electrical transformers and the like by the forma-
tion of channels therein. One such construction for example consists in
dividing the iron laminae of the core into several groups that are separated
from each other by means of rigid' metallic distance pieces, so arranged as to
form spaces or channels in the core which serve for ventilation.
My present invention has for its object to produce this result in a simpler
way, by employing in place of the said rigid distance pieces, lengths of sheet
metal that have their edges hent up and that are in some cases so arranged that
the bent up edges of one sheet interlock with or are enclosed by the edges of
another sheet, so as to form ventilating passages between them, the said lengths
of sheet metal being made either of equal or of unequal width.
On the accompanying drawing are shewn various arrangements for forming
ventilating passages in laminated cores according to my said invention. It will
be seen from these figures that some of the sheet iron laminae of the magnet
cores have their edges bent up thus forming ventilating passages between the
several groups of flat laminaę.
Figs. 1, 2, 3, 4 and 5 shew the manner of arranging the laminae which is
very advantageous for example for core-transformers.
The several sheet metal laminae aaa having their edges a¹a hent up, and
which may either be all of the same width or of unequal width, are arranged
symmetrically relatively to a central axis, and are secured together with the
groups of flat laminae by means of screw bolts bb.
As by the arrangement shewn in these figures there are in each group a
greater number of laminae at the middle part of the core than at the edges.
they will more effectually resist the comparatively strong compression exercised
by the bolts, so as not to become buckled and consequently separated from each
other at the edges, such as is the case with the usual arrangement of the laminae.
It will be seen that in Figs. 1 and 3 the channels are formed by alternately
bending down the edges of an upper sheet and bending up the edges of a lower
sheet, so that the edges interlock the edges of one sheet being enclosed by those
of another one; in Fig. 2 and Fig. 4 on the other hand the channels are formed
by bending up the edges of the one group of laminac only, the edges of the one
sheet being again enclosed by those of another one.
Figs. 6 and 7 shew arrangements applicable to other constructions of trans-
formers.

page_text: laminae a series of narrow sheets aa having their edges a¹ turned either down
as shewn, or up, while at Fig. 7 the laminae of the two groups have their edges
turned respectively up and down so as to interlock and enclose each other as
shown,
Having now particularly described and ascertained the nature of this in-
vention and in what manner the same is to be performed I declare that what
I claim is:-
1. In cores of transformers or the like formed of wrought iron laminae, the
production of ventilating passages by dividing the laminae into groups and
bending up the edges of some of the laminae of one or both of the contiguous
groups, substantially as described.
2. In laminated cores of transformers and the like constructed as set forth
in the First Claim, arranging the laminae with bent up edges so that they are
symmetrically situated relatively to a central axis, substantially as described.
Dated this 15th day of November 1899.
ABEL & IMRAY,
Agents for the Applicant.