Year: 1886

page_text: Date of Application, 23rd Oct., 1886.
Complete Left, 21st Apr., 1887.
Complete Accepted, 24th May, 1887,
Ì JOHN SAMUEL Ross of 15 Gunterstone Road West Kensington in the County
of Middlesex Electrician do hereby declare the nature of this invention to be as
follows:-
This Invention more particularly relates to improvements in the diaphragms or
tympans of telephone receivers and the said improvements may also be applied wholly
or in part to telephones of the transmitter class.
It has hitherto been found that diaphragms or tympans of the membraneous kind
and others of the type described and disclaimed in the Specifications of the "Bell
Patents" are all or nearly all subject to serious influences which have the effect of
injuring their utility.
For the purposes of my invention I will mention certain of the said serious
influences viz., atmospheric influences, and condensation on their surfaces of moisture
from the breath of individuals.
Now I overcome these difficulties in the following manner. For instance I give
the following illustration. I take or make a telephone of the well known type
consisting of a suitable case wherein are a membraneous or other type of diaphragm
stretched in a tense form before an electro magnet. In the centre of the diaphragm
and opposite the electro magnet is fastened its armature.
Now it is found that a diaphragm of this kind lessens in its elasticity and flexibility
owing to the reasons I have given. The consequence is that the electro magnet draws
the diaphragm on to it, and so causes the receiver for the time being to be practically
useless.
Now to overcome this difficulty I place at the back or further side of the diaphragm
a spiral or other suitable spring. One end of this spring may be very near the
diaphragm but not touching or it may be pressing against it, or it may be pressing on
a substance or substances which press against the diaphragm or it may be fastened to
the diaphragm if desired. The other end of the spring may be fastened or if desired
not fastened to the case of the instrument. This spring may be of such a degree of

page_text: resistance and so adjusted that when the diaphragm moves it moves, but does not
allow it to press on to the pole or poles of the electro magnet.
Let it be understood that by the use of spiral or other springs I am also enabled to
stretch diaphragms to degrees of tension which without the springs would cause them
to be useless for the transmission of speech.
According to my improvements I can also construct diaphragms in another way
but still using a spring or springs. For instance I take a diaphragm of wood or any
other suitable substance the object being that the wood or other suitable substance
shall not vibrate itself or at any rate as little as possible. To it I attach an armature
I then lay the whole in front of an electro magnet and on a spiral or other spring.
This diaphragm is not secured round its edges except as far as it presses against the
sides and the case. It may be fastened in a loose state if desired. I would remark
that the spiral spring or springs can be attached at both ends in any of the ways
herein before mentioned with regard to membraneous diaphragms.
It is advantageous to cause the spring to press this kind of diaphragm on an elastic
padding or surface fixed to the lid or upper part of the case.
I can also construct an improved diaphragm in another way. For this purpose I
take a thin disc of wood or other suitable substance of any suitable diameter and to
its centre I fasten the armature, I attach the whole by a membraneous substance of
larger proportions which can be stretched before the electro magnet to any desired
stiffness or if preferred may not be stretched in the sense of stretching. The spiral
spring is attached in the same fashion and by any of the preceding ways mentioned.
I may
here state that the springs may be attached in all my improved diaphragms,
in any way most convenient.
It is needless to say that a spiral or other spring can be applied according to my
improvements to all or nearly all kinds of telephones. It is also clear that all spiral
or other springs may be combined or fixed on one or both sides or at the edges of the
diaphragm and I do not confine myself to the number of springs used.
I may also use spiral springs in combination with flat springs or any other suitable
shape of spring or I may use flat or any other suitable shape of springs alone in fact
I may use any suitable form of spring or springs, nor do I confine myself to any
position of the spring or springs on the diaphragms or otherwise.
Dated this 23rd day of October 1886
TONGUE & BIRKBECK,
34, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: Improvements in Telephonic Apparatus.
I JOHN SAMUEL Ross of 15 Gunterstone Road West Kensington in the County
of Middlesex Electrician 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:-
For
This Invention more particularly relates to improvements in the diaphragms or
tympans of telephone receivers & the said improvements may also be applied wholly
or in part to telephones of the transmitter class. It has hitherto been found that
diaphragms or tympans of the membraneous kind & others of the type described
& disclaimed in the Specifications of the "Bell patents" are all or nearly all subject
to serious influences which have the effect of injuring their utility. For the purposes
of my invention I will mention certain of the said serious influences, viz., atmospheric
influences & condensation on their surfaces of moisture from the breath of
individuals. Now I overcome these difficulties in the following manner.
instance I give the following illustration. I take or make a telephone of the well
known type consisting of a suitable case wherein is a membraneous or other type of
diaphragm stretched in a tense form before an electro-magnet. In the centre of the
diaphragm & opposite the electro-magnet is fastened its armature. Now it is found
that a diaphragm of this kind varies and also increases in its elasticity & flexibility
owing to the reasons I have given. One of the consequences is that the electro-
magnet draws the diaphragm on to it & so causes the instrument for the tinie being
to be practically useless. Now to overcome this difficulty I place at the back or
further side of the diaphragm a spiral or other suitable spring. One end of this spring
may be very near the diaphragm but not touching or it may be pressing against it or
it may be pressing on a substance or substances which press against the diaphragm or
it may be fastened to the diaphragm if desired.
The other end of the spring may be fastened or if desired not fastened to the case
of the instrument. This spring may be of such a mechanical resistance & so
adjusted that when the diaphragm moves it moves but does not allow it to press on
to the pole or poles of the electro-magnet. The spring may be adjusted in more ways
than one as will be shewn in the drawings attached hereto and it will be clearly seen
that adjusting the spring or springs is equivalent to adjusting the diaphragm.
Let it be understood that by the use of sprial or other springs I am also enabled to
stretch diaphragms to degrees of tension which without the springs would cause them
to be useless for the transmission of speech and I am thereby enabled to utilize
diaphragms which without the aid of springs would utterly collapse on to their
electro-magnet or magnets. According to my improvements I can also construct
diaphragms in another way but still using a spring or springs. For instance I take
a diaphragm of wood or any other suitable substance the object heing that the wood
or other suitable substance shall not vibrate tympanically but shall wholly move up
& down. To the diaphragm I attach an armature I then lay the whole in front of

page_text: an electro-magnet & upon a spiral or other form of spring. This diaphragm is not
secured round its edges except as far as it presses against the case but it may be
fastened in a loose state if desired. I would remark that the spiral spring can be
attached at both ends in any of the ways hereinbefore mentioned with regard to
membraneous diaphragms. It is advantageous to cause the spring to press this kind
of diaphragm on an elastic padding or surface fixed to the mouthpiece or upper part
of the case. I can also construct an improved diaphragm in another way. For this
purpose I take a thin disc of wood or other suitable substance of any suitable
diameter & to its centre I fasten the armature. I attach the whole to a membraneous
substance of larger proportions which can be stretched before the electro-magnet to
any desired stiffness or if preferred may not be stretched in the sense of stretching.
The spiral spring is attached in the same fashion & by any of the preceding ways
mentioned. I may here state that the springs may be attached in my improved or
other diaphragms in any way most convenient. It is needless to say that a spiral or
other spring can be applied according to my improvements to all or nearly all kinds
of telephones. It is also clear that all spiral or other springs may be combined or
fixed on one or both sides or at the edges of the diaphragm & I do not confine
myself to the number of springs used. may also use spiral springs in combination
with flat springs or any other suitable shape of spring or I may use flat or any other
suitable shape of springs alone in fact I may use any suitable form of spring or
springs nor do I confine myself to any position of the spring or springs on the
diaphragms or otherwise. And so that my invention may be more fully comprehended
& explained I shall now proceed to describe the accompanying drawings in reference
thereto.
Figure 1 shews the telephone with the diaphragm secured round the edges & the
spring attachment on the inside. The adjustment of the spring on the diaphragm
may be effected by turning the screw the thread of which passes through a hole in
the diaphragm & armature & engages in the thread of a stud which is soldered to
the spring. The other end of the spring may be attached to the yoke of the magnet
or any other convenient place.
Figure 2 shows another form. In this the diaphragm is unsecured at its edges &
moves bodily like a piston the spring pressing the diaphragm against an elastic
surface of any description. By screwing the mouthpiece on the case a little more or
a little less the spring may be adjusted to the required resistance.
Figure 3 shews an instrument which may be a collapsible or other form of diaphragm
secured at its edges. On the inner side of the mouthpiece one end of a small arm
is fixed. The other end juts out to about the centre of the hole of the mouthpiece.
Thro' this latter end there is drilled a hole thro' which a screw passes with the
exception of its head which bears against the arm. The other end of this screw
engages (as previously mentioned) in the thread of a small stud which is attached to
one end of the spiral spring. The other end of the spiral spring is attached to the
diaphragm or armature in any way most convenient.
Figure 4 is a plan of the arm which is used for the purpose as mentioned with
regard to figure 3.
Figure 5 is nearly the same arrangement as figures 3 & 4 only in this case the
diaphragm is a hard disc or piston & vibrates wholly.
It is also unsecured round its edges but by the action of the spring simply presses
against a rim of any suitable substance.
Figures 6 & 7 are front & side views of a membraneous or other flexible diaphragm
secured with springs at one edge or side, the other end being attached in any
convenient way to the side of the case.
Figures 8 & 9 are also front & side views of a non flexible hard diaphragm which
vibrates wholly to the voice impulses and is also secured by any convenient process
with springs at the edges.
In figures 6 & 8 the arrangements for adjusting the resistances of the springs are
very similar to that of figure 3 with the exception that the screws instead of passing
thro' an arm as described pass through holes in the sides of the case.

page_text: "
In all the figures "a" represents the spring "b" the screw " C "the magnet "d"
the diaphragm e "the elastic surface "f" the mouthpiece "g"
"the arm or
bracket "the armature and the distances between the magnets & diaphragms
are adjusted by any of the commonly known methods.
The flexible diaphragms are also shewn as straight but they would in practice mostly
take a slightly curved form.
It is obvious all the above arrangements may be modified in many ways, for
example springs without any adjusting arrangements may be utilized. Any suitable
number of springs may be used. Other materials also, for example india-rubber may
serve the purpose of metal springs.
All the figures are shewn with armatures attached to membraneous or other
diaphragms not capable of inductive action upon a current of electricity. But
diaphragms capable of inductive action upon a current of electricity may be used
with advantage. As an illustration supposing I construct such a diaphragm say of
very thin iron or steel so thin indeed that when secured round its edges it is incapable
of retaining a sufficient rigidity before its electro-magnet but collapses on to it.
Then if I combine with this diaphragm any convenient form of my spring arrange-
ments exceedingly good results are attained. Forms of the inventor's spring
arrangements may be applied with advantage to nearly all forms of telephones without
indeed their diaphragms being necessarily collapsible..
It is to be here noted that the Inventor makes no claim to a telephone where a
diaphragm of a non flexible substance is used the said diaphragm being unsecured at
its edges having a piston like movement & being held in position by a flat spring or
springs.
Having now particularly described & ascertained the nature of my said invention
& in what manner the same is to be performed I declare that what I claim is
1. In a telephonic Instrument the combination of a diaphragm unsecured at its
edges with a spiral spring.
2. In a telephonic Instrument the combination of a diaphragm unsecured at its
edges with a spiral spring or its equivalent the mechanical resistance of which may
be regulated & adjusted.
3. In a telephonic Instrument the combination of a collapsible or other form of
diaphragm secured at its edges or any other part with a spiral spring or its
equivalent.
4. In a telephonic Instrument the combination of a collapsible or other form of
diaphragm secured at its edges or any other part with a spiral spring or its equivalent
the mechanical resistance of which may be regulated & adjusted.
5. The use of an arm, or its equivalent as & for the purposes herein shewn.
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