Year: 1885

page_text: I JOHN: SCUDAMORE SELLON, of Hatton Garden, in the County of Middlesex
Gentleman, do hereby declare the nature, of this invention to be as follows:
My Improvements relate to Microphones of the class that are more. especially
adapted to receive the direct impact of the sound waves and have for their object
making these instruments more reliable in their action and less liable to derange-
ment than is the case with microphones as heretofore constructed According to
my. Invention the contacts of the microphones are so arranged that they are
protected by their form or position from any deposition of globules of moisture,
preferably, by forming one or more portions of them in the shape of a tube within
which contact takes place. Thus for instance a short tube may be placed over thie
adjacent ends of two contact pieces which nearly meet' and the said tube, may be a
hole through a recess in a cylinder, bead, ball, cone, or other convenient piece of
carbon or other suitable conductor-Or a single rod of suitable conducting material
may be made to pass through the said bead or tube making internal: contact' there-
with the current being led to the said bead or tube by a light wire or spring or by
metallic foil. Or two fixed tubes or tubularly end fixed'pieces may be used' they
being caused to support a central piece shaped as a double cone or as a ball or of
other suitable form provided with a pair of protruding trunnions which fit into the
cavities and are protected by the said cavities and a wire, spring, or strip leads the
electric current to or from the said central piece. I find it preferable to give to
the said wire spring or strip a slight tension so that the tube, head, ball, or pièce is
not easily displaced or deranged by any puff of breath.from the speaker's mouth.
:
Dated this 18th day of November 1885-
'

page_text: I JOHN SCUDAMORE SELLON of Hatton Garden in the County of Middlesex
Gentleman 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:-
My Improvements relate to Microphones of the class that are adapted to receive
the direct impact of the sound waves and have for their object making the
instruments more reliable in their action and less liable to be damaged or deranged
by the breath of the person speaking to them than is the case with Microphones
as heretofore constructed. According to my Invention the contacts of the said
Microphones are so arranged that they are protected by their form or position from
any deposition upon them of moisture from the breath which protection is effected
preferably by forming one or more portions of them in the shape of a tube or
receptacle within which contact takes place. I will describe with reference to the
accompanying diagrams modes in which my Invention may be performed. Figure 1
shews an arrangement whereon a short tube a is placed over the adjacent ends of
two contact pieces b c which normally nearly meet and the said tube may be
formed by piercing a hole through a recess in the cylinder bead ball cone or other
convenient piece of carbon or other suitable conductor Or a single rod of suitable
conducting material may be made to pass through the said bead or tube making
internal contact therewith so as to constitute the contacts as illustrated by
Figures 2 and 3 and by Figures 4 and 5 wherein the bead or tube is marked b
and the rod is marked c the contacts being the meeting portion or portions of the
said parts b and c the current being led to the said bead or tube by a light wire
(as shown) or by a spring or by metallic foil. Figures and 3 only vary from
Figures 4 and 5 by the bead being in the one case barrel shaped and in the other
ball shaped to more completely obstruct the passage through which the air
waves pass.
Figure 6 shews a modification wherein there are two contact pieces c instead of
one piece and the bead b takes the form of a stud whose shank passes between the
ends of the pieces c-Or two or more fixed tubes or tubularly ended fixed pieces
may be used they being caused to support a central piece shaped as a double cone
or as a ball or of other suitable form provided with a pair of protruding trunnions
which fit into the cavities and are protected by the said cavities and a wire or strip
leads the electric current to or from the said central piece. I find it preferable to
give to the said wire or strip a slight tension or springiness so that the tube bead
ball or piece is not easily displaced or deranged by any puff of breath from the
speakers mouth.
Figure 7 and 8 shew an arrangement wherein the contact pieces are arranged
and protected as last described The central piece b is shewn as being ball shaped
and has two projecting trunnions 6' which enter recesses in the contact pieces c³ so
that the contacts which are between the opposite parts of the trunnions and the
interiors of the pieces c² are protected by being covered by the said pieces c³, c³ is

page_text: a wire for anchoring the central contact piece b. Figure 9 shews an arrangement
wherein the pieces c³ project into recesses in the ball b in which recesses the
contacts are made they being protected by the ball b. Of course the part b may be
of other than ball shape for example barrel shaped or pear shaped as indicated in
dotted lines-I have shewn two pieces c but it will be evident that there may be
three or more, corresponding projections or recesses being provided in corresponding
number on or in the ball b or its equivalent.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what
I claim is
In microphones for telephonic instruments the arrangement of the contacts
substantially as and for the purpose described and also the special arrangements
illustrated by way of examples in the accompanying Drawing.
'