Nov. 28, 1.950
A- MEYERHANS
TRANSFORMER
2,531,697
Filed Aug- 8. 1947
INVENTORv
ATTORNEYj
Patented Nov. 28, 1950
2,531,697
UNITED STATES PdTENT OFFICE
2,531,697
TRANSFORMER
August Meyerhans, Nussbaumen, near Baden,
Switzerland, assignor to Alstiengeseilsehaft
Brown, Boveri 5’; 623a, Baden, Switzerland
Application Angus. 8, 194?, Serial No. 767,462
in
November
1939
Section 1, Public Law 699, August 8, 1946
Patent expires November 2?), 1535.‘)
3 Claims.
(C1. 175——356)
1
When building transformers it has been usual
up to the present to make the iron core com
posed of columns for the windings and yolre parts
for the magnetic return flow out of sheet metal
stampings of diiferent length and width, which
2
plementary to the convex curvature of the col
umn, in order to facilitate the direct passage of
the flux between the column and the return flow
iron. The stampings of t e U-shaped packets of
the return ?ow iron can simply be stacked over a
are superposed in parallel planes and may be in
former corresponding to the circular periphery
terleaved. If in this arrangement the column
of the column. The stampings of the U-shaped
form is adapted as closely as possible in cross
yokes are held together by welding seams which
section to the circular form of the windings, the
are provided in places, preferably on the out
number of different sized stamping operations is l0 wardly disposed surfaces of the webs and/or
increased and the work entailed in stamping and
flanges. In the example shown, connecting strips
the ‘waste of sheet metal also becomes greater.
e1, e2 are used for the welding connection. The
The building up of the columns and the putting
strips e2 which are welded to the ?anges of the
together of the iron core entails much labor
U-shaped packets are used with the aid of strips
and is costly. The cost Of building up the core 15 63 welded to the end surfaces of the column and
is reduced by employing columns composed of
of bolts f for producing the pressure between the
metal sheets which are layered substantially
column and the U-shaped packets of the return
radially and which are connected at their end
flow iron. The active part of the transformer is
surfaces by welding seams. This method of build
inserted in a circular tank h. At least one sec
ing up columns is not only simple and cheap as 20 tor of the radially 1ouilt up column is replaced by
regards manufacture, it is also favorable from
a sector of insulating material
for instance
the magnetic and electric point of view. How
wood. This increases the space for the leads.
ever, the usual way of building up the return
It represents a bushing insulator.
flow is still unfavorable, as it entails a consider
The packets of the magnetic return flow iron
able amount of stamping work and a substantial
may be formed either of metal sheets stamped
waste of sheet metal and makes it necessary to
out in U-shape (Fig. 3) or of rectangular stamped
employ arrangements for supporting the wind
sheets built together and interleaved in U-form
ings.
(Fig. 4), whereupon they are welded in the man
The object of the present invention is to pro
ner described above. It is recommended to hold
vide a transformer having a column built up of
the stampings together at certain points by means
radial metal sheets, in which the described dis~
of bandages 91 (Figs. 1 and 3), which consist at
advantages are eliminated through the magnetic
least in part of insulating material. The band
return flow path being formed according to the
ages will suitably consist of cord windings which
invention of stampings which are built up in sub
are placed over angle pieces 92 of layered insu
stantially U-shaped packets and are pressed with 35 lating material, and cover the corners of the pack
their ?anges against the column.
In the accompanying drawing there is shown
ets of stampings.
Through the iron core being built up in ac
cordance with the invention the magnetic return
the above invention a single phase transformer.
flow part will also have a shape in which the
Figure l is a view in longitudinal section taken 4.0 stamping work is reduced to a minimum. Metal
on line I—| of Fig. 2 and Figure 2 is a view in
sheets stamped out in rectangular form and put
transverse cross-section taken on line 2-2 Of Fig.
together in U-form are held together very sim
1. Figures 3 and 4 show constructional details.
ply; no insulated screw connections are required
In the ?gures a represents the column of the
for the packets of stampings. The welding seams
iron core with radially-stacked stampings and the
hold the metal sheets together rigidly. When
concentric high and low voltage windings b, c.
the packets are composed of U-shaped stamp
The magnetic return flow \iron is formed of
ings, it becomes possible to use the rectangular
U-shaped yokes or packets of stampings 01, all
waste as column stampings for a smaller trans
to (is, which are arranged radially around the
former. The special form of welded connections
periphery of the column and are pressed with 50 in the case of the column and the return ?ow
their ?anges die. to (18s against the column, so
part enables the two parts to be united under
that they surround the windings. The end faces
pressure in a very simple manner. The building
dlb to dab of the flanges of the U-shaped packets
up of the transformer is thus greatly facilitated.
of stampings which confront the exterior surface
By means of wedge-shaped distance pieces n1,
of the column a have a concave curvature com
m (Fig. 1) pressure may be applied to the wind
diagrammatically as a construction example of
3
2,531,697
4
ings while the U-shaped packets are being pressed
plurality of U-shaped laminated yokes surround
against the column. As the packets of the re
turn flow part are individually pressed with suffi
cient forceagainst, the, column, the. induction of
the joint;may¢be was great as the induction ,of the
column. With a ?lling factor of 70% in the col
umn, referred to the full circular cross-section,
and. of 90% in the return connection yoke pieces,
ing said core with the yoke laminations arranged
in planes parallel with the core axis, the two end
flange portions of each said yoke confronting
said core and being provided with iconcave end
faces the curvature of which is the complement
»of the convex outer surface of said core so as
to lie directly against the core with the core and
the height of the yoke pieces H will be
10
yokelaminations arranged in substantially radial
alignment, spaced and confronting rigid strips
welded respectively to and extending axially out
ward from the opposite ends of said core and the
opposite ends of said yokes, and means extend
Dzcore diameter
H=0.195D.
As the normal transformer has a yoke height of
about D, for the transformer according to the .in
vention the overall height will be reduced by
2D—0.39D=1.61D.
ingybetween'and drawing said confronting core
and yoke strips towards one another thereby to
.draw the end faces of the ?ange portions of said
yokes into pressure contact with the outer sur
face.of..said core.
The manner in whichthe iron core is built up
' 2.‘ A transformer magnetic structure as de?ned
in accordance with the invention provides a
in claim 1 wherein thelaminations of each said
further- advantage as ‘regards cooling. 1 Cooling
yoke are constituted-by Uéshaped'stampings.
'3.» A‘ transformer magnetic structureas de?ned
in claim 1 wherein the yoke la-minationsare-con
tubes m may be disposed in'the spaces between
the ray-like or radially- arranged stamping pack
ets -of ‘the return'flow part. The cooling tubes
stituted'by rectangular stampings interleavedrto
m ‘may, also be‘ corrugated in the direction of 25 form the U-shaped‘ contourv of the yoke.
, AUGUST JMEYERHANS.
the longitudinal axes of the transformer.
T The "space occupied by --the transformer is in
.' REFERENCES CITED '
this way considerably reduced; its Weight is ‘also
reduced, to which the round form of the cas
ing also contributes, whereby reinforcement be
comes-‘unnecessary.
30
. The following references are of record-in the
file of this patent:
-
UNITED STATES PATENTS
"For building up athree-‘phase transformer‘ the
possibility is provided of mounting three single
‘Number
‘ Name
.‘Date
scribed axially one behind the other in one vessel.
850,863
' 854,278
T‘Wooldridge ______ __- Apr. ~16,‘ .1907
Darlington ________ _;;May 21, 19.07
The vconstruction according to the‘invention is
1,140,843
Nichols ___________ __".'May :25, 1915
particularly suitable‘ for enabling-transformers
1,623,345
Hopkins __________ __ Apr; 5, .1927
ofconsiderable output to be housed in a recum
' 2,107,973
Bajon ____________ __ Feb.‘ 23,1938
bent position on a-vvehicle frame,'so as‘to enable
the railway loading gauge to be utilized to‘ the
' 2,252,461
Franz ___________ __ Aug. .121, ‘1941
2,279,239
Meyerans __________ __~ Apr. 7:‘,‘1314l2
phase transformers of the construction above'de
-best>possib1e advantage. The bushinginsulators
FOREIGN‘ PATENTS
can ‘be arranged‘so as~t0 be distributed over-the
two ends of the transformer tank.
' I claim:
' 1;‘IIn atransformer, a magnetic structure com
prising a- radially laminated cylir'idrica'lv core, a
vNumber
45
; Country
.Date
' 421,512
‘Great Britain _,_______ Dec. 21‘, {19-34.
». 482,771
-GreatyBritain__.______» 'July ,8; @1937