A New or Improved Method of Making and Breaking Electric Circuits, and Apparatus therefor.
Year: 1891

page_text: Date of Application, 10th Dec., 1891
Complete Specification Left, 12th Sept., 1892-Accepted, 15th Oct., 1892
PROVISIONAL SPECIFICATION.
A New or Improved Method of Making and Breaking Electric
Circuits, and Apparatus therefor.
We, WILLIAM HENRY DINGLE, of 13 Hindon Street, London, S.W., and
JOHN MACKENZIE URQUHART, of 10 Denbigh Street, London, S.W., Electrical
Engineers, do hereby declare the nature of this invention to be as follows:-
This invention relates to a method of making and breaking electric circuits by
which great facility and efficiency of operation are obtained and to apparatus therefor
which is not only convenient in action but cheap in construction.
We employ two contact pieces as is usual and we cause the movable contact piece,
hereinafter referred to as the free piece, to reciprocate or approach to and recede
from the stationary contact piece, hereinafter styled the fixed piece, in a right line.
Of the two movements mentioned we cause the movement of the free piece to the
fixed piece to take place by external manual pressure and the movement of the free
piece from the fixed piece to take place by the action of a counter spring which is
compressed or deflected by the first movement mentioned namely that of the free
piece towards the fixed piece. In connection with the said free piece we employ a
detent to lock in in position when it has been moved into contact with the fixed
piece. The circuit is now made or closed and remains so until the detent is released.
To release the detent so as to break or open the circuit we employ what we may
term a releasing device which on being partially rotated or moved in an angular
direction frees the detent so as to enable the counter spring to force the free piece
away from the fixed piece and bring the parts again into their original position.
The essential elements of the said releasing device are a turning spring and a knob
or handle moving angularly and actuating the detent. The essential elements of
the said detent are a projection and two recessed parts or a recessed part and two
projections one or more of the said elements moving angularly to produce or
relinquish engagement under the influence of the releasing device at each movement
thereof.
A distinctive feature of our invention is that the angular movement of our
releasing device takes place in a plane at right angles to the direction of recipro-
cation of the free piece. In other words the direction of reciprocation of the free
piece is normal to the plane of movement of the releasing device.
In a modification of our invention we ensure the keeping of the contact surfaces
clean by causing the free piece to rotate or move angularly on making and or
breaking contact the said angular movement of the free piece being in a plane to
which the direction of reciprocation of the said free piece is normal; and this
angular movement we produce by one or both of the angular movements of the
releasing device.
We have hereinbefore spoken of the free piece being moved into contact by
external manual pressure and moved out of contact by the action of the counter
spring. It will of course be understood that the action of the functional elements
taking part in these movements may be reversed so that external manual pressure
shall break contact and the action of the counter spring make it.
We
In speaking of the essential elements of the detent, we mentioned recesses.
desire it to be understood that where the movable parts move within guides or the
like so as to be prevented from moving in more than one direction a recess, as the
word is generally understood, is not necessary as in such cases a simple flat surface
may fulfil the functions of and indeed constitute a recess.
We have hereinbefore spoken of two separate springs namely the counter spring
which serves to reciprocate the free piece and the turning spring which actuates the
We may however use a single spring as a substitute for these two springs
detent.

page_text: the said single spring fulfilling the functions of both the counter and the turning
springs. Thus if we employ as a counter spring a spiral spring with a set in it so
that it will tend to curl or uncurl then the said counter spring may also act as a
turning spring. In such a case one end of the spiral spring would be attached
to a fixed part and the other say to the free piece or a part in connection therewith
and the knob or handle of the relcasing device might also be the knob or handle by
which the free piece is actuated.
We have now described the nature of our invention and have done so in such
manner as to define its scope. We shall however by way of illustration add a brief
description of one way of carrying our invention into effect as embodied in an
actual switch.
Upon a suitable base we mount the fixed piece and over it we place a bridge
shaped frame to act partly as a guide and partly as a support for the free piece and
the parts connected therewith. Above the fixed piece is the free piece to which is
attached a rod passing up through the frame and ending in a push knob. In the
sides of the frame are also two vertical slots through which arms pass from the free
piece. The free ends of these arms cover or rest on spiral springs (constituting the
counter spring hereinbefore mentioned) which are compressed when the free piece is
pressed downwards into contact with the fixed piece. On the top of the frame
is fixed a slotted tube and concentrically within the said tube a sleeve or tube
similarly slotted. Within the latter is the push rod of the free piece having a
feather thereon which fits into the slots in the concentric tubes just mentioned. At
the upper end of the said push rod is a push knob. To the upper end of the inner
tube or sleeve is attached the releasing knob and to a pin on the under side of this
knob is affixed one end of the turning spring the other end of which is attached to
a pin on the outer tube hereinbefore referred to.
The action of this form of switch will now be easily understood. When it is
desired to make or close the circuit the free piece is pressed down into contact with
the fixed piece. When this is done the counter springs are compressed and the
feather on the push rod being now below the slots in the concentric tubes the inner
tube or sleeve is free to turn which it does under the influence of the turning spring.
The slot of the sleeve being now no longer coincident with the slot of the outer tube
the feather rests against the surface (the equivalent of a recess) of the lower end of
the sleeve so that the free and fixed pieces are locked or detained in contact. To break
or open the circuit all that now requires to be done is to turn the releasing knob (or
knob of the releasing device) in an angular direction so as to make the slot of the
sleeve coincide with the slot of the outer tube when the feather being freed the
compressed counter springs will force the feather up through the coincident slots'
and so move the free piece away from the fixed piece thus bringing the parts into
their original position again.
Deted this 10th J
1001
J. G. LORRAIN, M. Inst. E.E., M. Inst. M.E.,
Norfolk House, Norfolk Street, London, W.C., Applicants' Patent Agent.
COMPLETE SPECIFICATION.
A New or Improved Method of Making and Breaking Electric
Circuits, and Apparatus therefor.
We, WILLIAM HENRY DINGLE, of 13 Hindon Street, London, S.W., and
JOHN MACKENZIE URQUHART, of 14 Fermoy Road, Westbourne Park,
London, W. (late of 10 Denbigh Street, London, S.W.), Electrical Engineers,
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 :-
This invention relates to apparatus for making and breaking electric circuits
which is not only convenient in action but cheap in construction.

page_text: We employ two contact pieces as is usual; and we cause the movable contact
piece, hereinafter referred to as the free piece, to reciprocate or approach to and
recede from the stationary contact piece, hereinafter styled the fixed piece, in a
right line. Of the two movements mentioned, we cause the movement of the free
piece to the fixed piece to take place by external manual pressure, and the move-
ment of the free piece from the fixed piece to take place by the action of a counter
spring, which is compressed or deflected by the first movement mentioned, namely
that of the free piece towards the fixed piece. In connection with the said free
piece we employ a detent to lock it in position when it has been moved into contact
with the fixed piece. The circuit is now made or closed, and remains so until the
detent is released. To release the detent, so as to break or open the circuit, we
employ what we may term a releasing device, which, on being partially rotated or
moved in an angular direction, frees the detent so as to enable the counter spring to
force the free piece away from the fixed piece, and bring the parts again into their
original position. The essential elements of the said releasing device are a turning
spring and a knob or handle of the form of a sleeve or tube surrounding the free
piece or the rod or push attached thereto, both the said handle and spring moving
angularly and actuating the detent. The essential elements of the said detent are
a projection and two recessed parts or a recessed part and two projections one or
more of the said elements moving angularly to produce or relinquish engagement
under the influence of the releasing device at each movement thereof.
In a modification of our invention we ensure the keeping of the contact pieces
clean by causing the free piece to rotate or move angularly on making and or
breaking contact, the said angular movement of the free piece being in a plane to
which the direction of reciprocation of the said free piece is normal; and this
angular movement we produce by one or both of the angular movements of the
releasing device.
We have hereinhefore spoken of two separate springs namely the counter spring
which serves to reciprocate the free piece and the turning spring which actuates
the detent. We may however use a single spring as a substitute for these two
springs, the said single spring fulfilling the functions of both the counter and the
turning springs. Thus if we employ as a counter spring a spiral spring with a set
in it, so that it will tend to curl or uncurl, then the said counter spring may also act
as a turning spring. In such case one end of the spiral spring would be attached
to a fixed part and the other say to the free piece or a part in connection therewith
and the knob or handle of the releasing device might also be the knob or handle
by which the free piece is actuated.
We have herein before spoken of the free piece being moved into contact by
external manual pressure and moved out of contact by the action of the counter
spring. It will of course be understood that the action of the functional elements
taking part in these movements may be reversed, so that external manual pressure
shall break contact, and the action of the counter spring make it.
We
In speaking of the essential elements of the detent we mentioned recesses.
desire it to be understood that where the movable parts move within guides or the
like, so as to be prevented from moving in more than one line, a recess, as the word
is generally understood, is not necessary, as in such cases a simple shoulder or flat
surface may fulfil the functions of and practically constitute a recess.
We have now described our invention in such manner as to define its scope; but
in order that it may be more fully understood we shall now proceed to describe in
detail how it may be performed or carried into effect and for that purpose we shall
refer to the accompanying sheets of drawings in which similar letters of reference
apply to similar or equivalent parts.
Figures 1 to 5 illustrate the commonest form of our switch. Figure 1 is a front
elevation, and Figure 3 a vertical section, the several parts being in the position
which they occupy when the circuit is open or broken. Figure 2 is a front
elevation with the same parts in the position which they occupy when the circuit is

page_text: closed or made. Figure 4 is a plan and Figure 5 a horizontal section on the
line y
A is the base of the switch formed usually of slate, wood, china, or the like,
and B is the fixed piece mounted thereon and consisting in this case of two pieces
of sheet brass bent at a right angle and slit as shown in Figures 1 and 2. They are
fixed to the base by the screws hb which also serve as terminals for the wires or
leads. Over B is the bridge shaped frame C which acts partly as a guide and partly
as a support for the free piece D and the parts connected therewith. To Dis
attached the rod d passing upwards through the frame 'and'ending in the push
knob d'. In the sides of frame C are two vertical slots c (see Figure 3)
through which pass arms from the free piece D. These arms cover or rest
en the spiral springs E E (together constituting in this case the counter spring
herein before mentioned) which are compressed when the free piece D is "pressed
downwards into contact with the fixed piece B. On the top of the frame C is fixed
the outer slotted tube F and concentrically within this is the slotted 'sleeve or
tube G. Within the latter is the push rod a previously mentioned. Upond is the
feather which fits into the slots fand g. of the tubes F and G when the latter
are coincident and the parts are in the position which they occupy when the circuit'
is
open. To the upper part of the sleeve G is attached the releasing knob H and
to the pin on the under side of this knob is affixed one end of the turning 'spring J
the other end of which is attached to a rivet on the outer tube F.
The action of this form of switch will now be easily understood. When it is
desired to make or close the circuit the free piece D is pressed down into 'contact
with the fixed piece B. When this is done the counter springs E are compressed
and the feather d³ on the push rod d being now below the slots in the concentric
tubes F and G the inner tube or sleeve G is free to turn which it does under the
influence of the turning spring J. The slots of the sleeve G being now no longer
coincident with, the slot of the outer tube F the feather rests against the surface
(the equivalent of a recess) of the lower end of the sleeve G so that the free and
fixed pieces are locked or detained in contact. To break or open the circuit all
that now requires to be done is to turn the releasing knob H (or knob of the
releasing device) in an angular direction so as to make the slot of the sleeve G
coincide with the slot of the outer tube F when the feather being freed the com-
pressed counter springs E will force the feather d³ up through the coincident slots
and so move the free piece D away from the fixed piece B thus bringing the parts
into their original position again.
Figures 6, 7, 8, 9 and 10 represent another form of our invention which constitutes
that modification hereinbefore referred to by which we ensure the keeping of the
contact pieces clean by causing the free piece to rotate or move angularly on making
and or breaking circuit. Figure 6 is a front and Figure 7 a side elevation of this
form of our invention with the parts shown in the position which they occupy when
the circuit is open. Figure 8 is a section (on the line -y of Figure 9) with the
parts shown in the position which they occupy when the circuit is closed.
Figure 9 is a plan and Figure 10 is a section on the line z. z. of Figure 6. In
this form of switch, the counter spring E is sunk in the base of the switch, so as to
be compressed by the piston d', attached to the rod d, extending from the free piece D.
This free piece Ď is constructed of the shape of the frustrum of a cone, and is designed
to move angularly within the two brass contact pieces constituting the fixed piece B
hereinbefore mentioned. c is the frame, but it differs from the form of frame shown
in Figures 1 to 5, in that instead of having two vertical slots for the passage of
the arms d², it has a single slot c' at its upper surface, through which passes the
feather d³. To the top of D is attached the rod d, passing upwards through the
frame and ending in the push knob d'. On the top of the frame C is fixed the outer
slotted tube F, and concentrically within this is the slotted tube or sleeve G.
Within the latter is the push rod d, previously mentioned, upon which is the
feather d³, which latter fits into and works longitudinally in the slot y of the

page_text: sleeve G.
When the slot of the latter is coincident with the slot f in the outer
tube F, the feather d' also fits into the said slot f, as is shown in Figs. 6 and 7. To
the upper part of the sleeve G is attached the releasing knob H, and to the pin h
on the underside of this knob is affixed one end of the turning spring J, the other
end of which spring is attached to a rivet on the outer tube F. The lower end of
the sleeve G is in this form of switch continued down below the upper surface of
the frame C and below the outer tube F, so as to project below them. On the
underside of the top of the frame C is a projection or detent l.
The action of this form of switch will now be easily understood.
When it is desired to make or close the circuit, the free piece D is pressed down
by means of the knob d¹ into contact with the fixed piece B. When this is done,
the counter spring E is compressed, and the feather don the push rod d being now
below the slot in F, but still in the slot in G, the free piece D and the feather d
together with G are free to move angularly under the influence of the turning
spring J, which angular movement takes place until it is stopped by the feather d³
coming into contact with the projection. The free piece D is thus caused to
move angularly between the two pieces constituting the fixed piece B, and so keep
the contact surfaces clean. The slot of the tube G being now no longer coincident
with the slot of the outer tube F and the slot c', the top of the feather d³ rests
against the under surface, (the equivalent of a recess) of the top of the frame C,
and against the projection or detent, so that the free and fixed pieces are locked
or detained in contact. To break or open the circuit, all that is now required to
be done is to turn the releasing knob H (or knob of the releasing device) in an
angular direction so as to make the slot of the sleeve G in which is engaged the
feather coincide with the slot c¹ in the frame C and that in the outer tube F.
This angular motion is imparted to the free piece D causing it to rotate between
the two pieces constituting the fixed piece B. When the slot in the sleeve G
coincides with the slot in the frame C and the slot in the tube F the feather d' is
freed and the compressed counter spring E forces up the piston d' and the parts
attached thereto so that the feather d³ passes up through the coincident slots and
the free piece D is forced away from the fixed piece B thus bringing the parts into
their original position again as shown in Figure 6.
Figures 11, 12, 13 and 14 represent a third form of our invention wherein we use
a single spring as a substitute for the separate counter and turning springs. Of
these, Figure 11 is a front elevation, Figure 12 a side elevation, Figure 13 a section
with the parts shown in the position which they occupy when the circuit is closed,
and Figure 14 a plan section on the line W-W. This single spring is a helical
one E placed in a suitable recess in the base A underneath the fixed piece B. The
rod d³ extends downwards from the free piece D and terminates in a flat disc or
piston d. The upper end of the spring E is attached to the said piston d* and its
lower end to the base A in such a manner that a set is given to the spring E
making it tend to turn the piston d' relatively to the base A. The spring E at the
same time tends to push the piston upwards from the base A. The other portions
of this form of our switch resemble those of the form we have herein before described
with reference to Figures 6, 7, 8, 9 and 10, with the exception that the spring J is
omitted, it being unnecessary as the rotary motion of the free piece is produced
by the action of the set in the spring E. The action of this form of our switch
will be readily understood from the description of the form of switch described
with reference to Figures 6 to 10 the difference in the springs being borne in
mind.
It will be seen that the action of the spring E is such as to ensure a quick
break as it is called so that sparking at the contact surfaces is reduced to a
minimum.
Since filing our Provisional Specification we have ascertained that our invention,
in so far as the method is concerned, is not so widely novel as we had thought. We
therefore make no claim to the method but confine our claims to the apparatus.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In apparatus for making and breaking electric circuits, the combination,
substantially as set forth, of a fixed piece, a free piece, a detent and a releasing
device, the said releasing device being concentric with and surrounding the free
piece or the push rod.
2. The arrangement and combination of parts constituting the form of switch
substantially as set forth with reference to Figures 1 to 5 inclusive.
3. The arrangement and combination of parts constituting the form of switch
substantially as set forth with reference to Figures 6 to 10 inclusive.
4. The arrangement and combination of parts constituting the form of switch
substantially as set forth, with reference to Figures 11 to 14 inclusive.
Dated this 9th day of September 1892.
J. G. LORRAIN, M. Inst. E.E., M. Inst. M.E.,
Norfolk House, Norfolk Street, London, W.C., Chartered Patent Agent.