Improved Vacuum Drying Apparatus for Drying Bobbins, Armatures and the like of Dynamo Machines or Motors.
Year: 1898

page_text: Improved Vacuum Drying Apparatus for Drying Bobbins, Armatures
and the like of Dynamo Machines or Motors.
I, EMIL PASSBURG, of Brücken Allee 33, Berlin, in the Empire of Germany,
Engineer, do hereby declare the nature of this invention to be as follows:-
-
The bobbins, armatures and the like of dynamo machines or motors have been
hitherto dried under ordinary atmospheric pressure in regenerators, heated by
means of steam circulating in pipes.
•
For the good conductivity of armatures and bobbins it is indispensible that they
should be entirely dry. With the method of drying heretofore in use these parts
were exposed for a long time to the influence of heat, and in order to drive out
of them all the water they contained, they were exposed to a very high tempera-
ture without indeed always obtaining this result, the imperfection of the method,
exterior influences, change of degree of moisture in the atmospheric air, as well
as the changeable quality of the prime materials sometimes preventing their per-
fect drying, notwithstanding the high temperature and the long duration of the
drying process.
This long duration of the drying process in high temperature has moreover the
drawback of partly burning or destroying the organic ingredients of the coating
of the wires of the armatures and bobbins.
To avoid all these nuisances, I have constructed the hereinafter described appa-
ratus in which the matters are dried by vacuum whereby the purpose is obtained
with security and in a short time by means of low temperature.
The parts of dynamo machines to be dried are often of large dimensions and
note has been taken of this fact in the construction of the following apparatus
which has to withstand the exterior atmospheric pressure when the vacuum is
produced therein.
The drying apparatus, Figs. 1 to 4, consists of the cylindrical part A closed
on one side by the cover or wall D and on the other side by a door case B against
which the door T closes air tight by means of a gum elastic packing. Inside
the apparatus are arranged in a peculiar manner heating tubes s, s, or closed
heaters in which steam or other heating media circulate. Contrary to hitherto
known heating bodies, they are absolutely steam tight and permit in consequence
of their arrangement the entrance of large objects to be dried. Moreover the
apparatus is provided with an air pump junction e in connection with a condenser
and a vacuum pump. The objects to be dried are carried into the apparatus A
by means of carriages W or W₁. The heating tubes s or heaters h radiate their
heat upon the objects to be dried whereby the water under the vacuum in the
chamber A reduced to steam and can be collected and measured in a condensor.
Dated this 15th day of August 1898.

page_text: Improved Vacuum Drying Apparatus for Drying Bobbins, Armatures
and the like of Dynamo Machines or Motors.
I, EMIL PASSBURG, of Brücken Allee 33, Berlin, in the Empire of Germany,
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: —
The bobbins, armatures and the like of dynamo machines or motors, covered
wires and electric cables have been hitherto dried under ordinary atmosphere but
this purpose has only been obtained imperfectly or after a very prolonged period
of drying. For the good conductivity of the above mentioned objects it is absolutely
indispensible that they should be entirely dry. With the method of drying hereto-
fore in use they were exposed for a long time to the influence of heat, and in order to
drive out all the water they contained, they were exposed to a very high temperature
so that the insulating material of organic and other nature was overheated and con-
sequently damaged whilst the required result was by no means always obtained
owing to the imperfection of the method, exterior influences, change of degree
of moisture in the atmospheric air, as well as the changeable quality of the prime
materials sometimes preventing their perfect drying, notwithstanding the high
temperature and the long duration of the drying process.
To avoid all these inconveniences and in order to dry the respective objects
quickly and with a relatively low temperature I have constructed an apparatus
by which the drying in open air is excluded; the process is done under vacuum.
This apparatus is represented in the drawings left with my Provisional Specifica-
tion in which Fig. 1 is a longitudinal section on line 1-1 of Fig. 2. Fig. 2
a cross section on line 2-2 of Fig. 1, Figs. 3 and 4 are end views showing modified
forms of doors.
The apparatus consists of the cylindrical part A closed at one end by the cover
or wall and at the other end by a door T or it may also be closed air tight on
both sides by doors T.
The doors T can be of different known constructions. For example the cylin-
drical vacuum apparatus A is provided with an air tightly fastened door case B,
against which the door T closes air tightly by means of an india rubber packing.
This door T, is, as shown in Figs. 1 and 3 connected by links T¹ T¹ to a traveller E
suspended and movable on rails 7. It hangs so that on loosening the nuts K, K,
it falls automatically back from the door case B and can be then slid aside without
damaging the tightening material. When the apparatus is to be closed the
door T is slid in front of the opening and is driven against the packing
by means of the nuts K K. For small apparatus it is not requisite that
the door should hang on rails, but the door may be held by a frame G,
Fig. 4, hinged at G¹ to the door frame B and at G2 to the outside
face of the door. Inside the apparatus C heating tubes s s are arranged
or a steam mantel M or both combined. Instead of these heating tubes
there may be used hollow heating plates h and finally the heating effect may
also be obtained by placing the cylindrical apparatus C in masonry in order to
receive its heat from outside by fire gases, hot air or other heating means where-
with the above described inside heating systems also can be used for augmenting
the heating effect.
A practical heating means is especially steam, circulating at any tension in
the heating tubes s s or heating bodies h or in the steam mantel M.
The heat therefrom is radiated upon the objects to be dried inside the apparatus

page_text: whilst as high a vacuum as possible is made in the known manner inside the
apparatus and the vapours escape through a tube c¹ into a condensor or a vacuum
pump.
The objects to be dried may be introduced into the vacuum apparatus on cars
or small wagons W or W the wheels V or V1 of which can run on rails.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed I declare that what I claim
is: :-
1. A vacuum drying apparatus adapted to be closed hermetically at one side
by a cover D and at the other by a door T, or at both sides by doors T, and having
in its interior heating tubes s s or a steam mantel M, or the latter combined
with heating tubes ss or heating plates h in place of heating tubes for the purpose
of drying bobbins, armatures or other parts of dynamo electric machines or motors,
wires or cables under vacuum quickly and without damage to their insulation.
2. The mounting of the apparatus described in Claim 1 in masonry for the
purpose of utilizing fire gases, hot air or other exterior heating means with or
without the interior heating tubes or heating chambers, for the heating of the
apparatus.
D.L 1 11.
1-11 1
2000
HERBERT HADDAN & Co.,
Agents to Applicant,
18, Buckingham Street, Strand, W.C.