Year: 1899

page_text: Date of Application (in United Kingdom), 20th July, 1899
Complete Specification Lett, 18th Apr., 1900-Accepted, 19th May, 1900
We, GILBERT WRIGHT, of 409, Ross Avenue, and CHRISTIAN AALBORG, of
212, Franklin Street, both of Wilkinsburg, in the County of Allegheny and
State of Pennsylvania, U.S.A., Electrical Engineers, do hereby declare the nature
of this invention to be as follows; -
Our invention relates to electric switches and has for its object to provide
improved constructions of these devices which shall be specially suitable for use
with heavy currents although they are equally useful when applied to circuits
carrying small currents.
Hitherto switches when intended for use with very large currents have
required considerable power for their operation because the contacts and other
parts carrying the current have necessarily been made large and massive, and
where a spring contact is provided between two parts at the place where the
current is interrupted the spring will be very stiff by reason of the size of the
parts, such switches as those of the ordinary knife blade and jaw construction,
for example, have these disadvantages.
In the switches constructed according to the present invention the disadvan-
tages above mentioned are obviated by using a toggle joint to connect the
operating handle with the movable member of the switches.
The accompanying drawings shew various forms of circuit breakers constructed
according to our invention.
Figure 1 is a side elevation, and
Figure 2 a front view drawn to a reduced scale of one form of switch con-
structed according to our invention.
Figures 3 and 4 are similar views to Figures 1 and 2 respectively illustrating
another form.
Figure 5 is a side elevation, and
Figure 6 a front view of a double-throw switch constructed according to our
invention
Figure 7 being a detail view of the locking head forming part of the switch
mechanism.
I is the base which may be a switchboard panel and is constructed of insu-
lating material; 2 and 3 are the fixed terminals of the circuit; 4 is the movable
member for bridging the circuit terminals when the switch or breaker is closed,
and 5 is the operating handle.

page_text: Referring now particularly to Figures 1 and 2 the movable member 4 of the
switch is rigidly secured to arms pivoted at 7 to brackets 8 secured to the
base. Also pivoted to the brackets & at points 9 materially nearer the middle
of the member 4 than the pivots 7 of the arins 6 are two curved arms 10 formed
integral with the operating handle or lever 5.
A toggle lever 11 is pivoted at 12 to the lever 5 and at 13 to the arm 6, the
pivots being so arranged that when the switch is in its closed position as shewn
in Figure I the pivot 13 is slightly below the line joining the pivots 9 and 12.
The movable member of the switch is provided with a projection 14 which
engages with a projection 15 on the lever 5 when the switch has been moved
into its closed position. It will be clear without further description that owing
to the toggle lever connection the switch is very easily opened and closed
irrespective of its size and current-carrying capacity, and that when closed the
switch will be firmly held in that position by reason of the toggle joint having
passed slightly beyond its dead centre.
144
Referring now to Figures 3 and 4 the switch therein shewn differs slightly
from that previously described in the arrangement of the toggle mechanism.
It will be seen from an inspection of Figure 3 that the brackets 8 are extended
outward so that the pivot 9 of the lever 5 is outside the pivot 12. The length
of the toggle lever 11 and the position of the pivots are so arranged that the
pivot 12 will be slightly above the line joining the pivots 9 and 13 when the
switch is closed, and it will furthermore be seen that in order to open the switch
the handle 5 must be raised, whereas in the switch illustrated in Figure 1 the
handle 5 is lowered to open the switch.
Referring now to Figures 5, 6 and the base plate 1 is provided with three
contacts. 18, 19 and 20 arranged in line. Mounted on the base or attached to
the middle contact is a frame 21 to which is pivoted a bifurcated operating
lever 22 provided with a handle 23. Mounted on the same pivots is a bifurcated
arm 24 to which a movable member of the switch is pivotally attached. The
arm 24 has an enlarged outer end provided with a slot 25, curved to the arc
of a circle having its centre at the pivot of the arm. Pivotally mounted at the
outer end of the arm 24 beyond the slot is a locking head 26, the shape of
which is seen most clearly in Figure 7, and which has two projections 27 and
an opening of a trefoil shape with tliree recesses 29, 30 and 31. A pin secured
to the operating lever 15 passes through the slot 25 and the opening in the
head 26. The locking head 26 is furthermore connected to the arm 24 by a
spring 33, and a similar spring 34 connects the lever 24 with a point on the
movable member 4 located between its pivotal support and the base 1.
At each end of the supporting base I is a pair of standards 35 supporting a
pin or roller 36 with which the projecting arms 27 of the locking head cau
engage. Brackets 21 are furthermore provided with arms 37 at each side with
inwardly-bent ends 38 (see Figure 6) which act as guides for the movable
member 4 and prevent it tilting when it is being moved from one position to
the other.
The operation of the device is as follows:-
If the parts are in the position shewn in Figures 5 and 6 of the drawings
the terminals 18 and 19 are connected by the movable member 4, if the lever 22
be moved outward by means of its handle 23 the pin 32 will move in the slot 25
of the arm 24, and the head 26 will by means of the spring 33 be rotated so
that the pin 32 falls into the recess 30 of the opening in said locking head.
By this means the projecting portion 27 of the head withdrawn from engage-
ment with the roller or pin 36 and the lever 24 is thereby released. A further
movement of the lever 22 will carry with it the lever 24 and the spring 34 will
rock the movable member 4 on its pivot and hold it in such position that its
upward movement cannot be interfered with by the ends 38 of the upper guide
arms 27. A continuation of the movement of the lever 22 will carry the movable
member 4 upward into a position in front of the terminals 19 and 20, the move-

page_text: ment of the lever 24 being finally arrested by the engagement of the movable
member 4 with the upper pair of terminals. The pin 32 in this position of the
device will be in the recess 31 of the locking head, the other projection 27 of
said head engaging with the upper pin or roller 32, and thereby locking the
device in its new position. It is obvious that movement of the lever 22 in its
reverse direction, that is to say, in its downward direction will restore the device
to the position shewn in Figures 5 and 6.
Data the onth. .. T..1.. 1000
Improvements in Switches for Electric Circuits.
We, GILBERT WRIGHT, of 409, Ross Avenue, and CHRISTIAN AALBORG, of
212, Franklin Street, both of Wilkinsburg, in the County of Allegheny and
State of Pennsylvania, U.S.A., Electrical Engineers, do hereby declare the nature
of this invention and in what manner the same is to be performed to be par-
ticularly described and ascertained in and by the following statement:—
Our invention relates to electric switches and has for its object to provide
improved constructions of these devices which shall be specially suitable for use
with heavy currents although they are equally useful when applied to circuits
carrying small currents.
Hitherto switches when intended for use with very large currents have
required considerable power for their operation because the contacts and other
parts carrying the current have necessarily been made. large and massive, and
where a spring contact is provided between two parts at the place where the
current is interrupted the spring will be very stiff by reason of the size of the
parts, such switches as those of the ordinary knife blade and jaw construction,
for example, have these disadvantages.
In the switches constructed according to the present invention the disadvan-
tages above mentioned are obviated by using a toggle joint to connect the
operating handle with the movable member of the switches.
The drawings filed with Provisional Specification shew various forms of
circuit breakers constructed according to our invention.
Figure 1 is a side elevation, and
Figure 2 a front view drawn to a reduced scale of one form of switch con-
structed according to our invention.
Figures 3 and 4 are similar views to Figures 1 and 2 respectively illustrating
another form.
Figure 5 is a side elevation, and
Figure 6 a front view of a double-throw switch constructed according to our
invention
Figure 7 being a detail view of the locking head forming part of the switch
mechanism.
1 is the base which may be a switchboard panel and is constructed of insu-
lating material; 2 and 3 are the fixed terminals of the circuit: 4 is the movable
member for bridging the circuit terminals when the switch or breaker is closed,
and 5 is the operating handle.
Referring now particularly to Figures 1 and 2 the movable member 4 of the
switch is rigidly secured to arms 6 pivoted at 7 to brackets 8 secured to the
base 1. Also pivoted to the brackets 8 at points 9 materially nearer the middle

page_text: of the member 4 than the pivots 7 of the arms 6 are two curved arms 10 formed
integral with the operating handle or lever 5.
A toggle lever 11 is pivoted at 12 to the lever 5 and at 13 to the arm 6, the
pivots being so arranged that when the switch is in its closed position as shewn
in Figure the pivot 13 is slightly below the line joining the pivots 9 and 12.
The movable member 4 of the switch is provided with a projection 14 which
engages with a projection 15 on the lever 5 when the switch has been moved
into its closed position. It will be clear without further description that owing
to the toggle fever connection the switch is very easily opened and closed
irrespective of its size and current-carrying capacity, and that when closed the
switch will be firmly held in that position by reason of the toggle joint having
passed slightly beyond its dead centre.
Referring now to Figures 3 and 4 the switch therein shewn differs slightly
from that previously described in the arrangement of the toggle mechanism.
It will be seen from an inspection of Figure 3 that the brackets S are extended
outward so that the pivot 9 of the lever 5 is outside the pivot 12. The length
of the toggle lever 11 and the position of the pivots are so arranged that the
pivot 12 will be slightly above the line joining the pivots 9 and 13 when the
switch is closed, and it will furthermore be seen that in order to open the switch
the handle 5 must be raised, whereas in the switch illustrated in Figure 1 the
handle 5 is lowered to open the switch.
Referring now to Figures 5, 6 and 7 the base plate 1 is provided with three
contacts 18, 19 and 20 arranged in line. Mounted on the base or attached to
the middle contact is a frame 21 to which is pivoted a bifurcated operating
lever 22 provided with a handle 23. Mounted on the same pivots is a bifurcated
arm 24 to which the movable member 4 of the switch is pivotally attached. The
arm 24 has an enlarged outer end provided with a slot 25, curved to the arc
of a circle having its centre at the pivot of the arm. l'ivotally mounted at the
outer end of the arm 24 beyond the slot is a locking head 26, the shape of
which is seen most clearly in Figure 7, and which has two projections 27 and
an opening of a trefoil shape with three recesses 29, 30 and 31. A pin secured
to the operating lever 15 passes through the slot 25 and the opening in the
head 26. The locking head 26 is furthermore connected to the arm 24 by a
spring 33, and a similar spring 34 connects the lèver 24 with a point on the
movable member 4 located between its pivotal support and the base 1.
At each end of the supporting base I is a pair of standards 35 supporting a
pin or roller 36 with which the projecting arms 27 of the locking head can
engage. Brackets 21 are furthermore provided with arms 37 at each side with
inwardly-bent ends 38 (see Figure 6) which act as guides for the movable
member 4 and prevent it tilting when it is being moved from one position to
the other.
The operation of the device is as follows:
If the parts are in the position shewn in Figures 5 and 6 of the drawings
the terminals 18 and 19 are connected by the movable member 4, if the lever 22
be moved outward by means of its handle 23 the pin 32 will move in the slot 25
of the arm 24, and the head 26 will by means of the spring. 33 be rotated so
that the pin 32 falls into the recess 30 of the opening in said locking head.
By this means the projecting portion 27 of the head is withdrawn from engage-
ment with the roller or pin 36 and the lever 24 is thereby released. A further
movement of the lever 22 will carry with it the lever 24 and the spring 34 will
rock the movable member 4 on its pivot and hold it in such position that its
upward movement cannot be interfered with by the ends 38 of the upper guide
A continuation of the movement of the lever 22 will carry the movable
member 4 upward into a position in front of the terminals 19 and 20, the move-
ment of the lever 24 being finally arrested by the engagement of the movable
member 4 with the upper pair of terminals. The pin 32 in this position of the
device will be in the recess 31 of the locking head, the other projection 27 of
arms 37.

page_text: said head engaging with the upper pin or roller 32, and thereby locking the
device in its new position. It is obvious that movement of the lever 22 in its
reverse direction, that is to say, in its downward direction will restore the device
to the position shewn in Figures 5 and 6.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is:-
1. A double throw switch having three fixed contacts in one line the operating
lever being pivoted concentrically with an arm carrying the bridge piece of the
switch and a locking head, there being lost motion between said arm and lever
and a connection between the lever before the arm is caused to move the bridge
piece.
2. For a double throw switch a locking head as described and shewn in
Figure of the accompanying drawings and operating as specified.
3. Electric switches constructed according to any of the forms shewn in the
accompanying drawings and operating as described.
Da thin 10th dor of Ail 1900
W. P. THOMPSON & Co.,
Of London, Liverpool, Manchester and Birmingham.