Improvements in Electric Switches and in Apparatus for Connecting Electric Circuits.
Year: 1897

page_text: Date of Application, 21st Jan., 1897
Complete Specification Left, 20th Nov., 1897-Accepted, 21st Jan., 1898
PROVISIONAL SPECIFICATION.
Improvements in Electric Switches and in Apparatus for Connecting
Electric Circuits.
JOSEPH DEVONPORT FINNEY ANDREWS, 45, Fulham Park Gardens, Fulham,
London, S. W., Electrical Engineer, do hereby declare the nature of this inven-
tion to be as follows:-
Improvements in Electric Switches and in apparatus for connecting electric
circuits. My present invention relates to improvements in Electric Switches and
apparatus for connecting electric conductors either permanently or intermittently
as may be required. According to one form of my invention I construct an electric
Switch by providing a contact mounted on an insulator arranged to move along a
guide and to come against or between fixed contacts when pushed in one direction,
when the moving contact has made connection with the fixed contacts it is held
there by a bolt lever or spring catch which can be withdrawn by a suitable handle
and thus free the moveable contact which is arranged to fly free of a spring or
weight. Instead of the catch I may employ a lever or a pair of levers with a
spring or springs acting in such a way that when the sliding contact is against the
fixed contacts the spring causes the levers to press it on to them and when the
moveable contact is being withdrawn the levers are moved over the centre line of
force of the spring which then causes them to push the moveable contact away from
the fixed contacts. Instead of the levers I may arrange springs to oscillate and
have their direction of action reversed by the pull & push action of the moveable
contact.
The handle that operates the bolt or lever is preferably loosely connected to it
and is arranged to push the moveable contact into connection with the fixed contact
and also to insert the bolt or catch or reverse the levers or springs. Instead of the
handle being arranged to pull and push to operate the moveable contact I may
make it to oscillate on a centre and press the moveable contact against or between
the fixed contacts by means of a lever cam excentric or spiral in which case I
would not require the catch or levers but simply a spring acting in the opposite
direction to the cam or lever. I may construct my cam or lever of a piece of band
metal which passes through a hole in the guide of the moveable contact and when
it is turned a quarter of a circle it moves this moveable contact in opposition to a
spring into connection with the fixed contact or contacts, and flys away from them
when the action is reversed. I may arrange the spring operating the moveable
contact to convey the current to it in which case only one fixed contact is required.
Instead of the cam being constructed to act with an oscillating handle I may
arrange it for a turning handle in which case I would construct my handle with a
stem having a cam in the form of a spiral working in a corresponding fixed spiral.
I arrange my handle loose on the stem but provided with a stop which meets a
corresponding stop in the stem when it is turned, a spring is contrived between the
2 stops so that when the handle is turned the spring is compressed & causes the
stem to fly back after the moveable contact has left the fixed contacts where it
had been held by friction. I specially construct the moveable contact to have

page_text: more friction in the coming off direction than in the going on such as by providing
oblique saw cuts. I may modify this contrivance by providing the handle with a
screw thread fitting into a fixed nut and by arranging the spiral constructed
contact stem with stops to limit its free sideway motion. Thus when the handle is
turned it will force down the spiral stem which fits into it and by means of its own
screw thread bind it down onto the contacts or when the handle is turned in the
opposite direction it will remove the moveable contact from the fixed contacts. I
may construct my switch for either one or more circuits on single, double, or tripple
pole, in which case I provide a pair of fixed contacts for each pole and a moveable
contact to each pair carried preferably by the same insulator or I may construct my
switch for one pole with one or more interruptions in parallel or series and I may con-
struct my switch with a piece of metal strip or wire in the circuit which would
fuse & interrupt the circuit in the event of an excess of current, I prefer to protect
this strip of metal by forming it into a Ụ shape and inserting it into a hole or
tube of insulating material with a wedge between the legs of the U which binds
it against the insides of the hole. I may provide springs of strip metal on the
ends of the fuse wire and arrange the wedge to bind them in position, I prefer to
bend these springs against the outsides of the tube of insulating material so that it
can be inserted between fixed contacts. I may employ this fusible wire contrivance
independently of the switch; when I wish to control many circuits or combinations
of circuits or combinations of sources of supply of electricity, I arrange the switches
for the different circuits in close proximity & when each or any of
the circuits have more than one contact I prefer to arrange the con-
tacts in vertical or parallel rows and the moveable contact of the
switch would be mounted on a base or rod parallel with the series of contacts on
one side and a fixed continuous contact on the other so that it can be moved on
to any one of the contacts as may be desired. I may arrange the fixed continuous
contact common to 2 circuits. I may arrange the series of contacts for a resistance
in the circuit or for accumulators being charged or discharged. A combination of
parallel switches of this kind would consist of a circuit for a dynamo to charge
accumulators provided with a shunt resistance connected to a switch with many
contacts, the fixed continuous contact of this Switch may be common to a switch
having several contacts connected to several cells of a battery of accumulators for
charging, & this series of contacts may be common to a switch connected with the
lighting circuit for discharging the cells or connected with another dynamo which
would be provided with a switch to regulate the shunt resistance. I usually
arrange each of these parallel switches with the off position contact at the top so
that it can be arranged to connect the charging dynamo direct through to the
lighting circuit without connection with the accumulators.
1000
Improvements in Electric Switches and in Apparatus for Connecting
Electric Circuits.
JOSEPH DEVONPORT FINNEY ANDREWS, 45, Fulham Park Gardens, Fulham,
London, S.W., Electrical Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:
My present invention relates to improvements in electric switches and apparatus
for connecting electric conductors either permanently or intermittently as may be
required. According to one form of my invention I construct an electric switch by

page_text: providing a contact mounted on an insulator arranged to move along a guide and
to come against or between fixed contacts when pushed in one direction, when the
moving contact has made connection with the fixed contacts it is held there by a
bolt, lever, or spring catch which can be withdrawn by a suitable handle and thus
free the movable contact which is arranged to fly off by the force of a spring or
weight. Instead of the catch I may employ a lever or a pair of levers with a
spring or springs acting in such a way that when the sliding contact is against the
fixed contacts the spring causes the levers to press in on to them and when the
movable contact is being withdrawn the levers are moved over the centre line of
force of the spring which then causes them to push the movable contacts away
from the fixed contacts. Instead of the levers I may arrange springs to oscillate
and have their direction of action reversed by the pull and push action of the
movable contacts. The handle that operates the bolt or lever is preferably loosely
connected to it and is arranged to push the movable contact into connection with
the fixed contact and also to insert the bolt or catch or remove the levers or springs.
Instead of the handle being arranged to pull and push to operate the movable
contact I may make it to oscillate on a centre and press the movable contact
against or between the fixed contacts by means of a lever cam or eccentric, in
which case I would not require the catch or levers but simply a spring acting in
the opposite direction to the cam or lever. I may construct my cam or lever of a
piece of band metal which passes through a hole in the guide of the movable
contact, and when it is turned a quarter of a circle it moves the movable contact
in opposition to a spring into connection with the fixed contact or contacts, and
flies away from them when the action is reversed. I may arange the spring
operating the movable contact to convey the current to it in which case only one
fixed contact is required. Instead of the cam being constructed to act with an
oscillating handle, I may arrange it for a turning handle in which case I would
construct my handle with a stem having a cam in the form of a spiral working in
a corresponding fixed spiral. I arrange my handle loose on the stem but pro-
vided with a stop which meets a corresponding stop in the stem when it is turned,
a spring is contrived between the two stops so that when the handle is turned the
spring is compressed and causes the stem to fly back after the moveable contact
has left the fixed contacts where it had been held by friction. I may provide the
handle with a screw thread fitting into a fixed nut and by arranging the spiral
constructed contact stem with stops to limit its free sideway motion. Thus when
the handle is turned it will force down the spiral stem which fits into it and by
means of its own screw thread bind it down on to the contacts or when the handle
is turned in the opposite direction it will remove the movable contact from the fixed
contacts. I may construct my switch for either one or more circuits or single double
or triple pole, in which case I provide a pair of fixed contacts for each pole and a
movable contact to each pair carried preferably by the same insulator or I may
construct my switch for one pole with one or more interruptions in parallel or series
and I may construct a switch with a piece of metal or strip or wire in the circuit
which would fuse and interrupt the circuit in the event of an excess of current. I
prefer to protect this strip of metal by joining it into a U shape and inserting it
into a hole or tube of insulating material with a wedge between the legs of the U
which binds it against the insides of the hole. I may provide springs of strip
metal on the ends of the fuse wire and arrange the wedge to bind them in position.
I prefer to bend these springs against the outsides of the tube of insulating material,
so that it can be inserted between fixed contacts. I may employ this fusible wire
contrivance independently of the switch. When I wish to control many circuits
or combinations of circuits or combination of sources of supply of electricity I arrange
the switches for the different circuits in close proximity and when each or any of
the circuits have more than one contact I prefer to arrange the contacts in vertical
or parallel rows and the movable contact of the switch would be mounted on a bar
or rod parallel with the series of contacts on one side and a fixed continuous contact

page_text: on the other so that it can be moved on to any one of the contacts as may be
desired. I may arrange the fixed continuous contact common to 2 circuits. I
may arrange the series of contacts for a resistance in the circuit or for accumu-
lators being charged or discharged. A combination of parallel switches of this
kind would consist of a circuit for a dynamo to charge accumulators provided with
a shunt resistance connected to a switch with many contacts, the fixed continuous
contact of this switch may be common to a switch having several contacts connected
to several cells of a battery of accumulators for charging, and this series of
contacts may be common to a switch connected with the lighting circuit for dis-
charging the cells or connected with another dynamo which would be provided
with a switch to regulate the shunt resistance. I usually arrange each of these
parallel switches with the off position contact at the top so that it can be arranged
to connect the charging dynamo direct through to the lighting circuit without
connection with the accumulators.
Fig. 1 represents the modified form of my switch in which I use a catch to hold
the movable contact in connection with the fixed contacts. A is the movable con-
tact mounted on an insulator B arranged to slide freely along the guide C. and to
make connection between the contacts D D. The movement of the contact A in
the direction of the fixed contacts D D is effected by the handle F the stem H of
which passes down the centre of the guide C (which is square tubular) and is pro-
vided with a crosshead I which projects on either side through a slot in the square
guide tube so as to be capable of being pressed on to the insulator B. When the
insulator B carrying the contact A has been pressed into its lowest position by the
crosshead I on the handle stem H the formation J of the stem H impinges on the arm K
of the catch and causes the arm E to oscillate through a slot in the guide
tube Cand catch on to the insulator B and hold it in position. When the handle F
is withdrawn for the purpose of causing the switch to break circuit the crosshead I
meets with the arm K of the catch oscillates it on the centre pin L and moves it
off the contact insulator B which is thus released and being free, it is moved
upwards by the spring G and so breaks the circuit between the contacts D D.
In Figure 2 1 illustrate the modification of my switch in which levers are
employed. A A are the levers each of which is in the form of a U
and is hinged or pivoted to the handle stem H at E by the extremi-
ties of the legs a spring F is attached between the U levers at their
junction ends. This spring tends to draw the levers together against the pin E.
This pin is fixed in the sliding piece G to which the insulator carrying the movable
contact C is attached. This sliding pin E is free to move along the guide stem 1
which is tubular and is provided in the slots through which the pin E passes. These
slots form a guide to the pin and prevent the contact C turning round. The pin E
passes through the handle stem H which fits the tube I and when the handle K
is pushed into the guide tube the levers A A are oscillated by the pin E into a
position in line with one another in which position the spring F can exert no move-
ment on them, when however the handle H is withdrawn the levers are pulled
beyond their centre line and the spring causes them to exert pressure on the pin E
and push the contact C away from the fixed contacts D D. The handle stem H
is provided with a slot at the place where the pin E passes through it so that when
the contact moves by the force of the spring F. on the levers there is sufficient
freedom for the pin to move without moving the handle.
Fig. 3 represents a modification of my switch in which
instead of levers. The inovable contact C is mounted on
fixed to the carrying piece G and this is provided with 2
springs A. A are placed in compression between the hooks of these arms and the
guide stem I, upon which there are suitable projections to hold the springs in
position. The carrying piece G is provided with 2 screws or pins the guide tube I
and project beyond the inner surface and into the recessed portion of the handle
stem H so that when the handle is pulled or pushed the movable contact will be put
in or out of connection with the fixed contact D D and the length of the recess in
oscillate the springs AA
an insulator B which is
hooked arms E E. The

page_text: the handle stem will permit the springs to push the movable cantact away from
the fixed contacts sharply and independently.
Fig. 4 represents another modification of my switch in which I employ a cam A
pivoted to the guide stem at B to press the movable contact C against or between
the fixed contacts I) D. The cam is oscillated by the handle K attached to it. The
spring G moves the contact C away from the fixed contacts D D when it is not held
there by the cam A. Instead of a cam I may employ a flat strip of metal passed
through a square hole in the fixed stem as shewn at A, Fig. 5. This strip is
bent at right angles to form a handle K. The insulator E carrying the contact C
is pressed upwards by the spring G and when the handle K is oscillated the flat
strip A presses against the upper part of the square hole in the stem and the top
of the insulator which is consequently moved down carrying the contact C into
connection with the contacts D D.
stem H.
Fig. 6 illustrates the modification of my switch in which I employ a worm or
screw A to move the movable contact C into connection with the fixed contacts D D.
In the screw A is fixed a pin B which projects into a recessed part in the handle
When the handle is turned it meets with the pin and turns the screw-in
its nut E and carries the contact into connection with the contacts D D. There
is a spring I attached by one end to the screw A and by the other is the handle
stem H and when the handle is turned so as to break contact this spring is first
wound up until the handle stem meets with the pin B in the screw, when the
screw will be turned and cause the contact C to release its grip on the contacts D D
when the screw will fly round by the force of the spring until the pin B is stopped
by the limits of the slot in the handle stem.
.
I may modify this worm form of my switch as shewn in Fig. 7. In this form I
make the handle stem H the nut for the screw A and I screw this handle stem into
a fixed nut E outside of it. I fix the moveable contact C by an insertion to the
screw A. and I provide a pin B in the screw which when the screw is turned to one
side or the other will meet with either of the fixed pins F F and further movement
in the radial direction will be prevented, when however the handle K is turned so
as to move the screw. The screw A will be screwed into or out of the handle stem
and the contact C will be carried into connection with the contacts D D or break
connections. In both the modifications shown in Figs. 6 and 7 I prefer to make
the screws A with a quick thread.
When I desire to make my switch break two circuits as in the case of a double
pole switch I make the movable contact with the conductors in two parts C C as
in Fig. 8 shown in plan A B would be a pair of contacts of one circuit which would
be closed or broken by contact C and D & F the pair of contacts of the other circuit
closed and broken by the Contact C. I sometimes use this arrangement of my
contacts for high pressure for one circuit in which case I would connect con-
tact A&D by a permanent connection and I would thus gain four contact
breaking joints.
In Fig. 9 I illustrate my contrivance for breaking the circuit by means of a
U shaped wire A the current to which would pass in at one leg and out at the other
and in so doing a repellant action would be set up between the current in the legs
and the currents in the bridges and should fusion of the wire take place through
an excess of current passing through it this repellant action of the current in the
legs would tend to extinguish the arc that would be set up. I prefer to place an
insulating piece B between the legs of the U wire and I use this insulating piece
as a wedge to fix the wire into an insulating protecting tube C together with
suitable contacts D D. I insert a glass or mica stopper E in the end of the tube
to prevent the emission of sparks. I sometimes construct this fuse contrivance
with 2 pieces A A as shown in Fig. 10 in which case I place the U wire in
grooves B B in a slab of insulating material with a larger recess at the bend of
the U and I connect the legs of the U wires to suitable contacts.
In Fig. 11 I illustrate a combination of switches arranged to control a dynamo
and a set of accumulators. A A represents a series of contacts belonging to the

page_text: regulating resistance in the shunt circuit of a dynamo. The main terminals of
the dynamo are connected to the bar B and the return conductor would be con-
nected to the terminal E or earth connection. D) is a contact arranged to slide on
the fixed guide rod F' and connect the bar B with the Bar C when in the position
shown when however this contact is raised onto the contact G disconnection will be
effected with C. As the contact D is moved by a handle attached to it along the
guide rod its extremity H will slide over the contacts A A and reduce or increase
the resistance in the shunt circuit according to its position. The contacts I I are
in connection with the regulator cells of a battery of accumulators and the contact
Brush J is arranged on a guide bar K to slide in contact with them and the bar C
and thus convey the current from the dynamo to the accumulators. The top
contact L is free from connection and when the brush contact J occupies a position
on this connection with the dynamos is cut off from the accumulators. The
contact Brush M is also arranged on a guide bar N so as to slide over the contacts I
so as to convey the current from the accumulators to the bar O and thence through
the brush contact P to the series of contacts Q connected with a resistance in the
main circuit and to the lights or other applications. When the brush contact M
is at rest on the contact L there would be no current going to the lamp circuit from
the accumulators.
If Brush contact J is also on contact L then the current can pass direct from the
dynamo to the lamp circuit if however Brush contact l' be at rest on the contact R
the connection with the lamp circuit will be served and as this contact P is gradually
carried down by a handle fixed to it over the series of contacts Q the resistance in
the main circuit will be cut out: The return leads of the accumulator and the
lamp circuits are also connected to the Bar E.
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:
1st. The switches provided with a spring tending to force the moveable contact
away from the fixed contacts and cam or catch devices with handles to move it
into and retain it in connection in opposition to the spring as described and illus-
trated in Figs. 1, 4 & 5.
2nd. The switch provided with a worm and handle to turn same and carry the
moveable contact against fixed contacts. The handle also provided with a worm
or with a spring substantially as described and illustrated in Figs. 6 and 7.
3rd. The switches provided with oscillating levers or springs actuated by a pull
and push handle to effect the make and break of the circuit substantially as
described and illustrated in G Figs. 2 & 3.
4th. The arrangement of contacts arranged in series to interrupt high voltage
circuits, or two circuits as described and illustrated in Fig. 8.
5th. Effecting the interruptions of an electric circuit by a wire bent into U shape
that can melt under an excess of current as described and illustrated in
Figs. 9 and 10.
6th. Effecting the connection or disconnection or regulation of several circuits
in combination substantially as described and illustrated in Fig. 11.
16. Anohan 100