A Transformer of Electrical Currents for Surgical, Medical, and Dental Purposes.
Year: 1890

page_text: Date of Application, 12th Dec., 1890
Complete Specification Left, 13th June, 1891-Accepted, 18th July, 1891
DE MULTICATION.
A Transformer of Electrical Currents for Surgical, Medical, and
Dental Purposes.
I, ARNOLD BEAUMONT WOAKES, of 78 Harley Street, London, in the County
of Middlesex, Aural Surgeon, do hereby declare the nature of this invention to be
as follows:-
My invention relates to a means of utilizing an alternating electric current such
as is used in connection with house lighting, for the purposes of rendering
incandescent the platinum electrode of the electric cautery, for supplying a current
for surgical electric lamps, and for all purposes where it is necessary to use an
electric current varying in quality to that supplied for house lighting.
I attain this end by using a transformer the primary core of which-when used
with the reduced current (say of 100 volts) as supplied for house lighting is made
to offer sufficient resistance to this (100 volt) current, that no injurious or dangerous
effects from over heating can result, should the wires of the secondary coil be short-
circuited from any cause, and it is immaterial whether the magnetic core of the
transformer forms an open or closed circuit; neither is the shape, number, or
position of coils of material importance.
I construct my improved transformer in the following manner;- -I take a
bundle of soft iron wires to form the magnetic core, this I enclose in a hollow
cylinder of wood or other insulating material with a flange at each end, over this I
wind the primary core which consists of the requisite quantity of fine insulated
wire. Outside this primary core I place another thin hollow cylinder with flanges
as before, upon which is wound the secondary core. This core may consist of one
continuous coil of thick wire or of several layers of finer wire connected up in
parallel.
In order to regulate the strength of the current supplied to the cautery, lamp, or
other object, a resisting medium may be inserted in either the primary or secondary
circuit. The same result may likewise be obtained by causing the iron core in the
interior of the primary core to move in or out, or the secondary coil may be made
to alter its position relatively with regard to the primary coil and iron core.
Supposing that the electric lighting current supplied to a house has an intensity
of 100 volts for incandescent lighting may by my invention be further reduced to
an intensity of say 4 volts for the cautery, the ampere strength of course being at
the same time greatly increased.
When a continuous current is supplied I use any suitable automatic "make and
break" contact maker in connection with the primary circuit.
Dated this 12th day of December 1800
ROBT. ED. PHILLIPS, M.I.M.E.,
Consulting Engineer & Patent Agent,
Royal Courts Chambers, 70-72, Chancery Lane, London, W.C.,
Agent for the Applicant.
COMPLETE SPECIFICATION.
A Transformer of Electrical Currents for Surgical, Medical, and
Dental Purposes.
I, ARNOLD BEAUMONT WOAKES of 75 Harley Street, London, in the County
of Middlesex, Aural Surveyor, 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 :-

page_text: This invention relates to means of utilising an alternating electrical current, such
as is used for house lighting, for supplying electricity of the required intensity and
quantity for rendering incandescent the platinum used for electric cautery, or for
supplying current to surgical incandescent lamps; or for other purposes for which
may be required currents differing in quality from that supplied to the house. For
this purpose, I employ a converter or transformer in which a bundle of soft iron
wires forming the magnetic core, is enclosed in a hollow cylinder of wood or other
insulating material with a flange at each end. Upon this cylinder is wound the
desired quantity of insulated fine copper wire for forming the primary or inducting
coil. Outside this primary coil is placed another hollow cylinder of insulating
material and upon it are wound layers of secondary coils. For cautery, these coils
may consist of one continuous strand of thick wire or preferably of several layers of
finer wire connected in parallel.
In order to regulate the strength of current, the primary coil and iron core may
be moved longitudinally, so as to alter their relative position with regard to the
secondary coil.
The primary coil being connected to the conductor supplying the electricity, at,
say, an E.M.F. of 100 volts, the secondary coil for cautery should be such as to
have induced in it currents of about 20 amperès with E.M.F. of about 4 volts.
The resistance of the primary coil should be such that no harm can result from
overheating should the secondary coil be accidentally short circuited.
Fig. 1 of the accompanying drawings is a longitudinal section and Fig. 2 is a
transverse section of a transformer, according to my invention, arranged for surgical
purposes.
Fig. 3 is a plan of an intermitter to be used in combination with the transformer,
when the electrical supply current is continuous.
Referring to Figs. 1 and 2, the core A consisting of fine soft iron wires or laminae
insulated from each other contained in an insulating casing, has the primary coil B
wound on it and cased over. The core A and primary coil B are both attached to
an end piece C to which is fixed a dovetail slide D which can be slid to and fro
between guides E fixed on an insulating base F. To this base is fixed the secondary
coil or set of secondary coils G which remain at rest while the core and primary
coil can be slid to or fro within them in order to vary the tension and quantity of
the current. The intermitter shewn by Fig. 3 consists of an electro magnet H
having in front of its poles a steel blade spring K which can be more or less strained
by a screw nut L. Between the poles of the magnet is an adjustable contact
screw M.
When the magnet H is excited, it attracts the spring K which makes
contact with M thus short circuiting the current, whereupon the magnet ceasing to
attract with sufficient force, K springs away and is again attracted. Thus the
continuous current is rapidly intermitted. By the use of the variable transformer
alone when the electricity is supplied in alternating currents, or by its use in
combination with the intermitter when the circuit is continuous, the service supply
for lighting or other uses can be utilised for many surgical and analogous purposes,
such as for cautery, for giving shocks, for supplying a surgical lamp, for actuating
a dental drill or hammer, and the like.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I claim :
A transformer of electric currents for surgical, medical and dental purposes
wherein the iron core and primary coil wound thereon are arranged to be slid to or
fro within the secondary coil, substantially as described.
Dated this 13th day of June 1891.
ABEL & IMRAY,
Agents for the Applicant.