Improvements in or relating to Microphones and Telephones.
Year: 1893

page_text: Date of Application, 12th May, 1893-Accepted, 17th June, 1893
COMPLETE SPECIFICATION.
Improvements in or relating to Microphones and Telephones.
I, THEODOR PAETZOLD, of 1134 Reichenbergerstrasse, Berlin in the Empire of
Germany, Manufacturer 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 purpose of this invention is to improve the clearness and distinctness of
tones of the sound produced in telephones and microphones, and at the same time
to simplify the construction of such apparatus.
Reference being made to the annexed drawing
Fig. 1 is a vertical section of part of a telephonic transmitting apparatus.
Fig. 2 is a rear elevation of the lower part thereof.
The vibratory diaphragm m is provided on its front side for its protection
against mechanical injury with a wire grating d of any kind and of any suitable
material. Opposite the back of the diaphragm is a counter block k and between
the latter and the diaphragm are placed rings of felt or similar material r whose
interior is filled with powdered or granular carbon. The rings are pressed
against the diaphragm by the counter block which is fixed upon a plate s
regulated and held by a central pin p fastened in the frame or bracket b.
The hook to which the telephonic receiver is intended to be attached when not
in use, is pivoted at a and its rear arm is drawn down by spring t. This book
carries on its rear arm a pin ³, which when the hook is released from the weight
of the suspender receiver makes contact with the contact springs l. l.; and when
the hook is weighted makes contact with a similar spring. The contacts // are
in the communicating circuit. The contact in the call circuit.
Contacts in these circuits are also controlled by the button x and the springf
which this button moves when pressed by hand. When at rest the spring f is in
contact with springy and the circuit is complete for speaking or hearing. Pressure
on the button disconnects this circuit and brings the spring into contact with
the spring completing the circuit in the calling line.
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The apparatus may be constructed with or without induction coil i.
Having now particularly described and ascertained the nature of this said inven-
tion and in what manner the same is to be performed I declare that what I
claim is ;-
1) In a telephonic receiver or transmitter, a protecting wire trellis or the like in
front of the vibratory membrane.
2) In a telephonic or microphonic transmitter, the combination with a diaphragm
or membrane of a counter-block k supported substantially as described by pin p
and bracket b, and rings of felt or the like filled with powdered or granular
carbon between the diaphragm or membrane and the counter block.
3) In a telephonic apparatus, the combination of hook k pivoted at a, pin h¹ and
contact springs 1, 1, 1, substantially as and for the purpose herein described and
illustrated.
4) In a telephonic apparatus, the combination of the button a, the spring f and
the contacts y and z substantially as and for the purpose herein described and
illustrated.
R. HADDAN,
Herbert Haddan & Co.,
18, Buckingham Street, Strand, London, Agent for Applicant.